diff --git a/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/cntr.c b/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/cntr.c
index 5d2d5ac8af9..5345b479725 100644
--- a/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/cntr.c
+++ b/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/cntr.c
@@ -5,13 +5,14 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-#include <hal/nrf_rtc.h>
+#include <stdint.h>
 
 #include "hal/cntr.h"
 
 #include "hal/debug.h"
 
 #if !defined(CONFIG_BT_CTLR_NRF_GRTC)
+#include <hal/nrf_rtc.h>
 #ifndef NRF_RTC
 #if defined(CONFIG_SOC_COMPATIBLE_NRF54LX)
 #define NRF_RTC NRF_RTC10
@@ -19,6 +20,8 @@
 #define NRF_RTC NRF_RTC0
 #endif /* !CONFIG_SOC_COMPATIBLE_NRF54LX */
 #endif /* !NRF_RTC */
+#else /* CONFIG_BT_CTLR_NRF_GRTC */
+#include <hal/nrf_grtc.h>
 #endif /* CONFIG_BT_CTLR_NRF_GRTC */
 
 static uint8_t _refcount;
@@ -32,6 +35,7 @@ void cntr_init(void)
 			 GRTC_MODE_SYSCOUNTEREN_Msk;
 
 	NRF_GRTC->TASKS_CLEAR = 1U;
+	nrf_grtc_task_trigger(NRF_GRTC, NRF_GRTC_TASK_CLEAR);
 
 #if defined(CONFIG_BT_CTLR_NRF_GRTC_KEEPRUNNING)
 	NRF_GRTC->KEEPRUNNING =
@@ -52,8 +56,18 @@ void cntr_init(void)
 #endif /* CONFIG_BT_CTLR_NRF_GRTC_START */
 
 	NRF_GRTC->EVENTS_COMPARE[HAL_CNTR_GRTC_CC_IDX_TICKER] = 0U;
+	nrf_grtc_event_clear(NRF_GRTC, HAL_CNTR_GRTC_EVENT_COMPARE_TICKER);
 
+	/* FIXME: Replace with nrf_grtc_int_enable when is available,
+	 *        with ability to select/set IRQ group.
+	 *        Shared interrupts is an option? It may add ISR latencies?
+	 */
 	NRF_GRTC->INTENSET1 = HAL_CNTR_GRTC_INTENSET_COMPARE_TICKER_Msk;
+	if (IS_ENABLED(CONFIG_SOC_SERIES_BSIM_NRF54LX)) {
+		extern void nhw_GRTC_regw_sideeffects_INTENSET(uint32_t inst, uint32_t n);
+
+		nhw_GRTC_regw_sideeffects_INTENSET(0, 1);
+	}
 
 #if defined(CONFIG_BT_CTLR_NRF_GRTC_START)
 	NRF_GRTC->MODE = ((GRTC_MODE_SYSCOUNTEREN_Enabled <<
@@ -72,6 +86,7 @@ void cntr_init(void)
 			 0U;
 
 	NRF_GRTC->TASKS_START = 1U;
+	nrf_grtc_task_trigger(NRF_GRTC, NRF_GRTC_TASK_START);
 #endif /* CONFIG_BT_CTLR_NRF_GRTC_START */
 
 #else /* !CONFIG_BT_CTLR_NRF_GRTC */
@@ -125,8 +140,11 @@ uint32_t cntr_cnt_get(void)
 	 */
 	do {
 		cntr_h = NRF_GRTC->SYSCOUNTER[1].SYSCOUNTERH;
+		cntr_h = nrf_grtc_sys_counter_high_get(NRF_GRTC);
 		cntr_l = NRF_GRTC->SYSCOUNTER[1].SYSCOUNTERL;
+		cntr_l = nrf_grtc_sys_counter_low_get(NRF_GRTC);
 		cntr_h_overflow = NRF_GRTC->SYSCOUNTER[1].SYSCOUNTERH;
+		cntr_h_overflow = nrf_grtc_sys_counter_high_get(NRF_GRTC);
 	} while ((cntr_h & GRTC_SYSCOUNTER_SYSCOUNTERH_BUSY_Msk) ||
 		 (cntr_h_overflow & GRTC_SYSCOUNTER_SYSCOUNTERH_OVERFLOW_Msk));
 
@@ -149,13 +167,17 @@ void cntr_cmp_set(uint8_t cmp, uint32_t value)
 	/* Read current syscounter value */
 	do {
 		cntr_h = NRF_GRTC->SYSCOUNTER[1].SYSCOUNTERH;
+		cntr_h = nrf_grtc_sys_counter_high_get(NRF_GRTC);
 		cntr_l = NRF_GRTC->SYSCOUNTER[1].SYSCOUNTERL;
+		cntr_l = nrf_grtc_sys_counter_low_get(NRF_GRTC);
 		cntr_h_overflow = NRF_GRTC->SYSCOUNTER[1].SYSCOUNTERH;
+		cntr_h_overflow = nrf_grtc_sys_counter_high_get(NRF_GRTC);
 	} while ((cntr_h & GRTC_SYSCOUNTER_SYSCOUNTERH_BUSY_Msk) ||
 		 (cntr_h_overflow & GRTC_SYSCOUNTER_SYSCOUNTERH_OVERFLOW_Msk));
 
 	/* Disable capture/compare */
 	NRF_GRTC->CC[cmp].CCEN = 0U;
+	nrf_grtc_sys_counter_compare_event_disable(NRF_GRTC, cmp);
 
 	/* Set a stale value in capture value */
 	stale = cntr_l - 1U;
@@ -163,6 +185,7 @@ void cntr_cmp_set(uint8_t cmp, uint32_t value)
 
 	/* Trigger a capture */
 	NRF_GRTC->TASKS_CAPTURE[cmp] = 1U;
+	nrf_grtc_task_trigger(NRF_GRTC, (NRF_GRTC_TASK_CAPTURE_0 + (cmp * sizeof(uint32_t))));
 
 	/* Wait to get a new L value */
 	do {
@@ -182,9 +205,12 @@ void cntr_cmp_set(uint8_t cmp, uint32_t value)
 	/* Set compare register values */
 	NRF_GRTC->CC[cmp].CCL = value;
 	NRF_GRTC->CC[cmp].CCH = cntr_h & GRTC_CC_CCH_CCH_Msk;
+	nrf_grtc_sys_counter_cc_set(NRF_GRTC, cmp,
+				    ((((uint64_t)cntr_h & GRTC_CC_CCH_CCH_Msk) << 32) | value));
 
 	/* Enable compare */
 	NRF_GRTC->CC[cmp].CCEN = 1U;
+	nrf_grtc_sys_counter_compare_event_enable(NRF_GRTC, cmp);
 
 #else /* !CONFIG_BT_CTLR_NRF_GRTC */
 	nrf_rtc_cc_set(NRF_RTC, cmp, value);
diff --git a/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/cntr.h b/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/cntr.h
index d6777d086a1..5e294af589a 100644
--- a/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/cntr.h
+++ b/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/cntr.h
@@ -6,7 +6,11 @@
 
 #if defined(CONFIG_BT_CTLR_NRF_GRTC)
 #define HAL_CNTR_GRTC_CC_IDX_TICKER 10
+#define HAL_CNTR_GRTC_EVENT_COMPARE_TICKER \
+	_CONCAT(NRF_GRTC_EVENT_COMPARE_, HAL_CNTR_GRTC_CC_IDX_TICKER)
 #define HAL_CNTR_GRTC_INTENSET_COMPARE_TICKER_Msk \
 	_CONCAT(_CONCAT(GRTC_INTENSET1_COMPARE, HAL_CNTR_GRTC_CC_IDX_TICKER), _Msk)
 #define HAL_CNTR_GRTC_CC_IDX_RADIO  11
+#define HAL_CNTR_GRTC_EVENT_COMPARE_RADIO \
+	_CONCAT(NRF_GRTC_EVENT_COMPARE_, HAL_CNTR_GRTC_CC_IDX_RADIO)
 #endif /* CONFIG_BT_CTLR_NRF_GRTC */
diff --git a/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/radio/radio.c b/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/radio/radio.c
index ebca4872074..4386afb0d0e 100644
--- a/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/radio/radio.c
+++ b/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/radio/radio.c
@@ -1183,6 +1183,7 @@ void radio_tmr_status_reset(void)
 {
 #if defined(CONFIG_BT_CTLR_NRF_GRTC)
 	NRF_GRTC->CC[HAL_CNTR_GRTC_CC_IDX_RADIO].CCEN = 0U;
+	nrf_grtc_sys_counter_compare_event_disable(NRF_GRTC, HAL_CNTR_GRTC_CC_IDX_RADIO);
 #else /* !CONFIG_BT_CTLR_NRF_GRTC */
 	nrf_rtc_event_disable(NRF_RTC, RTC_EVTENCLR_COMPARE2_Msk);
 #endif  /* !CONFIG_BT_CTLR_NRF_GRTC */
@@ -1226,6 +1227,7 @@ void radio_tmr_tx_status_reset(void)
 {
 #if defined(CONFIG_BT_CTLR_NRF_GRTC)
 	NRF_GRTC->CC[HAL_CNTR_GRTC_CC_IDX_RADIO].CCEN = 0U;
+	nrf_grtc_sys_counter_compare_event_disable(NRF_GRTC, HAL_CNTR_GRTC_CC_IDX_RADIO);
 #else /* !CONFIG_BT_CTLR_NRF_GRTC */
 	nrf_rtc_event_disable(NRF_RTC, RTC_EVTENCLR_COMPARE2_Msk);
 #endif  /* !CONFIG_BT_CTLR_NRF_GRTC */
@@ -1273,6 +1275,7 @@ void radio_tmr_rx_status_reset(void)
 {
 #if defined(CONFIG_BT_CTLR_NRF_GRTC)
 	NRF_GRTC->CC[HAL_CNTR_GRTC_CC_IDX_RADIO].CCEN = 0U;
+	nrf_grtc_sys_counter_compare_event_disable(NRF_GRTC, HAL_CNTR_GRTC_CC_IDX_RADIO);
 #else /* !CONFIG_BT_CTLR_NRF_GRTC */
 	nrf_rtc_event_disable(NRF_RTC, RTC_EVTENCLR_COMPARE2_Msk);
 #endif  /* !CONFIG_BT_CTLR_NRF_GRTC */
@@ -1393,6 +1396,7 @@ uint32_t radio_tmr_start(uint8_t trx, uint32_t ticks_start, uint32_t remainder)
 
 	/* Disable capture/compare */
 	NRF_GRTC->CC[HAL_CNTR_GRTC_CC_IDX_RADIO].CCEN = 0U;
+	nrf_grtc_sys_counter_compare_event_disable(NRF_GRTC, HAL_CNTR_GRTC_CC_IDX_RADIO);
 
 	/* NOTE: We are going to use TASKS_CAPTURE to read current
 	 *       SYSCOUNTER H and L, so that COMPARE registers can be set
@@ -1402,8 +1406,11 @@ uint32_t radio_tmr_start(uint8_t trx, uint32_t ticks_start, uint32_t remainder)
 	/* Read current syscounter value */
 	do {
 		cntr_h = NRF_GRTC->SYSCOUNTER[1].SYSCOUNTERH;
+		cntr_h = nrf_grtc_sys_counter_high_get(NRF_GRTC);
 		cntr_l = NRF_GRTC->SYSCOUNTER[1].SYSCOUNTERL;
+		cntr_l = nrf_grtc_sys_counter_low_get(NRF_GRTC);
 		cntr_h_overflow = NRF_GRTC->SYSCOUNTER[1].SYSCOUNTERH;
+		cntr_h_overflow = nrf_grtc_sys_counter_high_get(NRF_GRTC);
 	} while ((cntr_h & GRTC_SYSCOUNTER_SYSCOUNTERH_BUSY_Msk) ||
 		 (cntr_h_overflow & GRTC_SYSCOUNTER_SYSCOUNTERH_OVERFLOW_Msk));
 
@@ -1413,6 +1420,8 @@ uint32_t radio_tmr_start(uint8_t trx, uint32_t ticks_start, uint32_t remainder)
 
 	/* Trigger a capture */
 	NRF_GRTC->TASKS_CAPTURE[HAL_CNTR_GRTC_CC_IDX_RADIO] = 1U;
+	nrf_grtc_task_trigger(NRF_GRTC, (NRF_GRTC_TASK_CAPTURE_0 +
+					 (HAL_CNTR_GRTC_CC_IDX_RADIO * sizeof(uint32_t))));
 
 	/* Wait to get a new L value */
 	do {
@@ -1431,13 +1440,18 @@ uint32_t radio_tmr_start(uint8_t trx, uint32_t ticks_start, uint32_t remainder)
 
 	/* Clear compare event, if any */
 	NRF_GRTC->EVENTS_COMPARE[HAL_CNTR_GRTC_CC_IDX_RADIO] = 0U;
+	nrf_grtc_event_clear(NRF_GRTC, HAL_CNTR_GRTC_EVENT_COMPARE_RADIO);
 
 	/* Set compare register values */
 	NRF_GRTC->CC[HAL_CNTR_GRTC_CC_IDX_RADIO].CCL = ticks_start;
 	NRF_GRTC->CC[HAL_CNTR_GRTC_CC_IDX_RADIO].CCH = cntr_h & GRTC_CC_CCH_CCH_Msk;
+	nrf_grtc_sys_counter_cc_set(NRF_GRTC, HAL_CNTR_GRTC_CC_IDX_RADIO,
+				    ((((uint64_t)cntr_h & GRTC_CC_CCH_CCH_Msk) << 32) |
+				     ticks_start));
 
 	/* Enable compare */
 	NRF_GRTC->CC[HAL_CNTR_GRTC_CC_IDX_RADIO].CCEN = 1U;
+	nrf_grtc_sys_counter_compare_event_enable(NRF_GRTC, HAL_CNTR_GRTC_CC_IDX_RADIO);
 
 #else /* !CONFIG_BT_CTLR_NRF_GRTC */
 	nrf_rtc_cc_set(NRF_RTC, 2, ticks_start);
@@ -1513,6 +1527,7 @@ uint32_t radio_tmr_start_tick(uint8_t trx, uint32_t ticks_start)
 
 	/* Disable capture/compare */
 	NRF_GRTC->CC[HAL_CNTR_GRTC_CC_IDX_RADIO].CCEN = 0U;
+	nrf_grtc_sys_counter_compare_event_disable(NRF_GRTC, HAL_CNTR_GRTC_CC_IDX_RADIO);
 
 	/* NOTE: We are going to use TASKS_CAPTURE to read current
 	 *       SYSCOUNTER H and L, so that COMPARE registers can be set
@@ -1522,8 +1537,11 @@ uint32_t radio_tmr_start_tick(uint8_t trx, uint32_t ticks_start)
 	/* Read current syscounter value */
 	do {
 		cntr_h = NRF_GRTC->SYSCOUNTER[1].SYSCOUNTERH;
+		cntr_h = nrf_grtc_sys_counter_high_get(NRF_GRTC);
 		cntr_l = NRF_GRTC->SYSCOUNTER[1].SYSCOUNTERL;
+		cntr_l = nrf_grtc_sys_counter_low_get(NRF_GRTC);
 		cntr_h_overflow = NRF_GRTC->SYSCOUNTER[1].SYSCOUNTERH;
+		cntr_h_overflow = nrf_grtc_sys_counter_high_get(NRF_GRTC);
 	} while ((cntr_h & GRTC_SYSCOUNTER_SYSCOUNTERH_BUSY_Msk) ||
 		 (cntr_h_overflow & GRTC_SYSCOUNTER_SYSCOUNTERH_OVERFLOW_Msk));
 
@@ -1533,6 +1551,8 @@ uint32_t radio_tmr_start_tick(uint8_t trx, uint32_t ticks_start)
 
 	/* Trigger a capture */
 	NRF_GRTC->TASKS_CAPTURE[HAL_CNTR_GRTC_CC_IDX_RADIO] = 1U;
+	nrf_grtc_task_trigger(NRF_GRTC, (NRF_GRTC_TASK_CAPTURE_0 +
+					 (HAL_CNTR_GRTC_CC_IDX_RADIO * sizeof(uint32_t))));
 
 	/* Wait to get a new L value */
 	do {
@@ -1551,13 +1571,18 @@ uint32_t radio_tmr_start_tick(uint8_t trx, uint32_t ticks_start)
 
 	/* Clear compare event, if any */
 	NRF_GRTC->EVENTS_COMPARE[HAL_CNTR_GRTC_CC_IDX_RADIO] = 0U;
+	nrf_grtc_event_clear(NRF_GRTC, HAL_CNTR_GRTC_EVENT_COMPARE_RADIO);
 
 	/* Set compare register values */
 	NRF_GRTC->CC[HAL_CNTR_GRTC_CC_IDX_RADIO].CCL = ticks_start;
 	NRF_GRTC->CC[HAL_CNTR_GRTC_CC_IDX_RADIO].CCH = cntr_h & GRTC_CC_CCH_CCH_Msk;
+	nrf_grtc_sys_counter_cc_set(NRF_GRTC, HAL_CNTR_GRTC_CC_IDX_RADIO,
+				    ((((uint64_t)cntr_h & GRTC_CC_CCH_CCH_Msk) << 32) |
+				     ticks_start));
 
 	/* Enable compare */
 	NRF_GRTC->CC[HAL_CNTR_GRTC_CC_IDX_RADIO].CCEN = 1U;
+	nrf_grtc_sys_counter_compare_event_enable(NRF_GRTC, HAL_CNTR_GRTC_CC_IDX_RADIO);
 
 #else /* !CONFIG_BT_CTLR_NRF_GRTC */
 	nrf_rtc_cc_set(NRF_RTC, 2, ticks_start);
diff --git a/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/radio/radio_nrf5.h b/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/radio/radio_nrf5.h
index b07ce22172f..88b6939cd20 100644
--- a/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/radio/radio_nrf5.h
+++ b/subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/radio/radio_nrf5.h
@@ -70,6 +70,9 @@
 /* This has to come before the ppi/dppi includes below. */
 #include "radio_nrf5_fem.h"
 
+/* Include RTC/GRTC Compare Index used to Trigger Radio TXEN/RXEN */
+#include "hal/cntr.h"
+
 #if defined(PPI_PRESENT)
 #include <hal/nrf_ppi.h>
 #include "radio_nrf5_ppi_resources.h"
diff --git a/subsys/bluetooth/controller/ll_sw/nordic/lll/lll.c b/subsys/bluetooth/controller/ll_sw/nordic/lll/lll.c
index 4100eaf9cf5..fb14fee01f6 100644
--- a/subsys/bluetooth/controller/ll_sw/nordic/lll/lll.c
+++ b/subsys/bluetooth/controller/ll_sw/nordic/lll/lll.c
@@ -122,6 +122,7 @@ static void rtc0_nrf5_isr(const void *arg)
 #if defined(CONFIG_BT_CTLR_NRF_GRTC)
 	if (NRF_GRTC->EVENTS_COMPARE[HAL_CNTR_GRTC_CC_IDX_TICKER]) {
 		NRF_GRTC->EVENTS_COMPARE[HAL_CNTR_GRTC_CC_IDX_TICKER] = 0U;
+		nrf_grtc_event_clear(NRF_GRTC, HAL_CNTR_GRTC_EVENT_COMPARE_TICKER);
 #else /* !CONFIG_BT_CTLR_NRF_GRTC */
 	if (NRF_RTC->EVENTS_COMPARE[0]) {
 		nrf_rtc_event_clear(NRF_RTC, NRF_RTC_EVENT_COMPARE_0);