diff --git a/soc/silabs/silabs_siwx91x/Kconfig b/soc/silabs/silabs_siwx91x/Kconfig
index 34ea8e2dfa4..458d55dc2c8 100644
--- a/soc/silabs/silabs_siwx91x/Kconfig
+++ b/soc/silabs/silabs_siwx91x/Kconfig
@@ -19,4 +19,12 @@ config SOC_SILABS_SLEEPTIMER
 	help
 	  The Sleeptimer HAL module is used for SIWX91X.
 
+config SIWX91X_NWP_INIT_PRIORITY
+	int "SiWx91x Network Processor init priority"
+	default 39
+	help
+	  Initialization priority of the SiWx91x Network Processor. NWP init must
+	  have a higher priority than services that depend on it, such as Bluetooth,
+	  Wi-Fi and crypto.
+
 endif # SOC_FAMILY_SILABS_SIWX91X
diff --git a/soc/silabs/silabs_siwx91x/siwg917/nwp.c b/soc/silabs/silabs_siwx91x/siwg917/nwp.c
index 3882fcf07fb..71a20ac33c3 100644
--- a/soc/silabs/silabs_siwx91x/siwg917/nwp.c
+++ b/soc/silabs/silabs_siwx91x/siwg917/nwp.c
@@ -193,7 +193,11 @@ static int siwg917_nwp_init(void)
 
 	return 0;
 }
-SYS_INIT(siwg917_nwp_init, POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE);
+#if defined(CONFIG_MBEDTLS_INIT)
+BUILD_ASSERT(CONFIG_SIWX91X_NWP_INIT_PRIORITY < CONFIG_KERNEL_INIT_PRIORITY_DEFAULT,
+	     "mbed TLS must be initialized after the NWP.");
+#endif
+SYS_INIT(siwg917_nwp_init, POST_KERNEL, CONFIG_SIWX91X_NWP_INIT_PRIORITY);
 
 /* IRQn 74 is used for communication with co-processor */
 Z_ISR_DECLARE(74, 0, IRQ074_Handler, 0);