diff --git a/include/shell/shell.h b/include/shell/shell.h
index cc8786498d7..731e1ec66b5 100644
--- a/include/shell/shell.h
+++ b/include/shell/shell.h
@@ -292,16 +292,19 @@ struct shell_transport_api {
 	int (*uninit)(const struct shell_transport *transport);
 
 	/**
-	 * @brief Function for reconfiguring the transport to work in blocking
-	 * mode.
+	 * @brief Function for enabling transport in given TX mode.
 	 *
-	 * @param transport  Pointer to the transfer instance.
-	 * @param blocking   If true, the transport is enabled in blocking mode.
+	 * Function can be used to reconfigure TX to work in blocking mode.
+	 *
+	 * @param transport   Pointer to the transfer instance.
+	 * @param blocking_tx If true, the transport TX is enabled in blocking
+	 *		      mode.
 	 *
 	 * @return NRF_SUCCESS on successful enabling, error otherwise (also if
 	 * not supported).
 	 */
-	int (*enable)(const struct shell_transport *transport, bool blocking);
+	int (*enable)(const struct shell_transport *transport,
+		      bool blocking_tx);
 
 	/**
 	 * @brief Function for writing data to the transport interface.
diff --git a/include/shell/shell_uart.h b/include/shell/shell_uart.h
index 1559ee9b352..fc9edfb8d34 100644
--- a/include/shell/shell_uart.h
+++ b/include/shell/shell_uart.h
@@ -26,7 +26,7 @@ struct shell_uart_ctrl_blk {
 	shell_transport_handler_t handler;
 	void *context;
 	atomic_t tx_busy;
-	bool blocking;
+	bool blocking_tx;
 #ifdef CONFIG_MCUMGR_SMP_SHELL
 	struct smp_shell_data smp;
 #endif /* CONFIG_MCUMGR_SMP_SHELL */
diff --git a/subsys/shell/shell.c b/subsys/shell/shell.c
index 1bb6b502b68..4abb17444e4 100644
--- a/subsys/shell/shell.c
+++ b/subsys/shell/shell.c
@@ -1035,14 +1035,16 @@ static void transport_evt_handler(enum shell_transport_evt evt_type, void *ctx)
 
 static void shell_log_process(const struct shell *shell)
 {
-	bool processed;
+	bool processed = false;
 	int signaled = 0;
 	int result;
 
 	do {
-		shell_cmd_line_erase(shell);
+		if (!IS_ENABLED(CONFIG_LOG_IMMEDIATE)) {
+			shell_cmd_line_erase(shell);
 
-		processed = shell_log_backend_process(shell->log_backend);
+			processed = shell_log_backend_process(shell->log_backend);
+		}
 
 		struct k_poll_signal *signal =
 			&shell->ctx->signals[SHELL_SIGNAL_RXRDY];
@@ -1167,7 +1169,7 @@ void shell_thread(void *shell_handle, void *arg_log_backend,
 				  &shell->ctx->signals[i]);
 	}
 
-	err = shell_start(shell);
+	err = shell->iface->api->enable(shell->iface, false);
 	if (err != 0) {
 		return;
 	}
@@ -1177,6 +1179,12 @@ void shell_thread(void *shell_handle, void *arg_log_backend,
 					 log_level);
 	}
 
+	/* Enable shell and print prompt. */
+	err = shell_start(shell);
+	if (err != 0) {
+		return;
+	}
+
 	while (true) {
 		/* waiting for all signals except SHELL_SIGNAL_TXDONE */
 		err = k_poll(shell->ctx->events, SHELL_SIGNAL_TXDONE,
@@ -1250,17 +1258,10 @@ int shell_start(const struct shell *shell)
 	__ASSERT_NO_MSG(shell);
 	__ASSERT_NO_MSG(shell->ctx && shell->iface && shell->prompt);
 
-	int err;
-
 	if (shell->ctx->state != SHELL_STATE_INITIALIZED) {
 		return -ENOTSUP;
 	}
 
-	err = shell->iface->api->enable(shell->iface, false);
-	if (err != 0) {
-		return err;
-	}
-
 	if (IS_ENABLED(CONFIG_SHELL_VT100_COLORS)) {
 		shell_vt100_color_set(shell, SHELL_NORMAL);
 	}
diff --git a/subsys/shell/shell_log_backend.c b/subsys/shell/shell_log_backend.c
index 3a388671d97..7413e2562a6 100644
--- a/subsys/shell/shell_log_backend.c
+++ b/subsys/shell/shell_log_backend.c
@@ -18,10 +18,23 @@ int shell_log_backend_output_func(u8_t *data, size_t length, void *ctx)
 void shell_log_backend_enable(const struct shell_log_backend *backend,
 			      void *ctx, u32_t init_log_level)
 {
-	log_backend_enable(backend->backend, ctx, init_log_level);
-	log_output_ctx_set(backend->log_output, ctx);
+	int err = 0;
+
+	if (IS_ENABLED(CONFIG_LOG_IMMEDIATE)) {
+		const struct shell *shell;
+
+		shell = (const struct shell *)ctx;
+
+		/* Reenable transport in blocking mode */
+		err = shell->iface->api->enable(shell->iface, true);
+	}
+
+	if (err == 0) {
+		log_backend_enable(backend->backend, ctx, init_log_level);
+		log_output_ctx_set(backend->log_output, ctx);
 	backend->control_block->dropped_cnt = 0;
-	backend->control_block->state = SHELL_LOG_BACKEND_ENABLED;
+		backend->control_block->state = SHELL_LOG_BACKEND_ENABLED;
+	}
 }
 
 static struct log_msg *msg_from_fifo(const struct shell_log_backend *backend)
@@ -179,9 +192,10 @@ static void put(const struct log_backend *const backend, struct log_msg *msg)
 		}
 
 		break;
-
 	case SHELL_LOG_BACKEND_PANIC:
+		shell_cmd_line_erase(shell);
 		msg_process(shell->log_backend->log_output, msg, colors);
+
 		break;
 
 	case SHELL_LOG_BACKEND_DISABLED:
@@ -193,11 +207,67 @@ static void put(const struct log_backend *const backend, struct log_msg *msg)
 	}
 }
 
+static void put_sync_string(const struct log_backend *const backend,
+			    struct log_msg_ids src_level, u32_t timestamp,
+			    const char *fmt, va_list ap)
+{
+	const struct shell *shell = (const struct shell *)backend->cb->ctx;
+	u32_t key;
+	u32_t flags = LOG_OUTPUT_FLAG_LEVEL |
+		      LOG_OUTPUT_FLAG_TIMESTAMP |
+		      LOG_OUTPUT_FLAG_FORMAT_TIMESTAMP;
+
+	if (IS_ENABLED(CONFIG_SHELL_VT100_COLORS)) {
+		flags |= LOG_OUTPUT_FLAG_COLORS;
+	}
+
+	key = irq_lock();
+	shell_cmd_line_erase(shell);
+	log_output_string(shell->log_backend->log_output, src_level, timestamp,
+			  fmt, ap, flags);
+	shell_print_prompt_and_cmd(shell);
+	irq_unlock(key);
+}
+
+static void put_sync_hexdump(const struct log_backend *const backend,
+			 struct log_msg_ids src_level, u32_t timestamp,
+			 const char *metadata, const u8_t *data, u32_t length)
+{
+	const struct shell *shell = (const struct shell *)backend->cb->ctx;
+	struct k_poll_signal *signal;
+	u32_t key;
+	u32_t flags = LOG_OUTPUT_FLAG_LEVEL |
+		      LOG_OUTPUT_FLAG_TIMESTAMP |
+		      LOG_OUTPUT_FLAG_FORMAT_TIMESTAMP;
+
+	if (IS_ENABLED(CONFIG_SHELL_VT100_COLORS)) {
+		flags |= LOG_OUTPUT_FLAG_COLORS;
+	}
+
+	key = irq_lock();
+	shell_cmd_line_erase(shell);
+	log_output_hexdump(shell->log_backend->log_output, src_level, timestamp,
+			   metadata, data, length, flags);
+	irq_unlock(key);
+
+	/* Even though log message is handled notify shell thread which
+	 * will print command buffer after the log message.
+	 */
+	if (IS_ENABLED(CONFIG_MULTITHREADING)) {
+		signal = &shell->ctx->signals[SHELL_SIGNAL_LOG_MSG];
+		k_poll_signal_raise(signal, 0);
+	}
+}
+
 static void panic(const struct log_backend *const backend)
 {
 	const struct shell *shell = (const struct shell *)backend->cb->ctx;
 	int err;
 
+	if (IS_ENABLED(CONFIG_LOG_IMMEDIATE)) {
+		return;
+	}
+
 	err = shell->iface->api->enable(shell->iface, true);
 
 	if (err == 0) {
@@ -230,7 +300,11 @@ static void dropped(const struct log_backend *const backend, u32_t cnt)
 }
 
 const struct log_backend_api log_backend_shell_api = {
-	.put = put,
+	.put = IS_ENABLED(CONFIG_LOG_IMMEDIATE) ? NULL : put,
+	.put_sync_string = IS_ENABLED(CONFIG_LOG_IMMEDIATE) ?
+			put_sync_string : NULL,
+	.put_sync_hexdump = IS_ENABLED(CONFIG_LOG_IMMEDIATE) ?
+			put_sync_hexdump : NULL,
+	.dropped = dropped,
 	.panic = panic,
-	.dropped = dropped
 };
diff --git a/subsys/shell/shell_uart.c b/subsys/shell/shell_uart.c
index 9dca12f1a2e..ca14310fec4 100644
--- a/subsys/shell/shell_uart.c
+++ b/subsys/shell/shell_uart.c
@@ -180,18 +180,14 @@ static int uninit(const struct shell_transport *transport)
 	return 0;
 }
 
-static int enable(const struct shell_transport *transport, bool blocking)
+static int enable(const struct shell_transport *transport, bool blocking_tx)
 {
 	const struct shell_uart *sh_uart = (struct shell_uart *)transport->ctx;
 
-	sh_uart->ctrl_blk->blocking = blocking;
+	sh_uart->ctrl_blk->blocking_tx = blocking_tx;
 
-	if (blocking) {
-		if (!IS_ENABLED(CONFIG_SHELL_BACKEND_SERIAL_INTERRUPT_DRIVEN)) {
-			k_timer_stop(sh_uart->timer);
-		}
+	if (blocking_tx) {
 #ifdef CONFIG_SHELL_BACKEND_SERIAL_INTERRUPT_DRIVEN
-		uart_irq_rx_disable(sh_uart->ctrl_blk->dev);
 		uart_irq_tx_disable(sh_uart->ctrl_blk->dev);
 #endif
 	}
@@ -218,7 +214,7 @@ static int write(const struct shell_transport *transport,
 	const u8_t *data8 = (const u8_t *)data;
 
 	if (IS_ENABLED(CONFIG_SHELL_BACKEND_SERIAL_INTERRUPT_DRIVEN) &&
-		!sh_uart->ctrl_blk->blocking) {
+		!sh_uart->ctrl_blk->blocking_tx) {
 		irq_write(sh_uart, data, length, cnt);
 	} else {
 		for (size_t i = 0; i < length; i++) {