diff --git a/srsue/hdr/stack/mac_nr/mac_nr.h b/srsue/hdr/stack/mac_nr/mac_nr.h
index 5e4dd84c2..e782973cd 100644
--- a/srsue/hdr/stack/mac_nr/mac_nr.h
+++ b/srsue/hdr/stack/mac_nr/mac_nr.h
@@ -35,6 +35,7 @@ struct mac_nr_args_t {};
 class mac_nr final : public mac_interface_phy_nr,
                      public mac_interface_rrc_nr,
                      public mac_interface_proc_ra_nr,
+                     public mac_interface_sr_nr,
                      public mac_interface_mux_nr
 {
 public:
@@ -85,6 +86,9 @@ public:
   uint64_t get_contention_id();
   uint16_t get_crnti();
 
+  /// procedure sr nr interface
+  void start_ra() { proc_ra.start_by_mac(); }
+
   /// Interface for MUX
   srsran::mac_sch_subpdu_nr::lcg_bsr_t generate_sbsr();
 
diff --git a/srsue/hdr/stack/mac_nr/mac_nr_interfaces.h b/srsue/hdr/stack/mac_nr/mac_nr_interfaces.h
index a4c673157..e791bd002 100644
--- a/srsue/hdr/stack/mac_nr/mac_nr_interfaces.h
+++ b/srsue/hdr/stack/mac_nr/mac_nr_interfaces.h
@@ -39,7 +39,17 @@ public:
 };
 
 /**
- * @brief Interface from MAC NR parent class to mux ubclass
+ * @brief Interface from MAC NR parent class to SR subclass
+ */
+class mac_interface_sr_nr
+{
+public:
+  // MUX can query MAC for current C-RNTI for Msg3 transmission
+  virtual void start_ra() = 0;
+};
+
+/**
+ * @brief Interface from MAC NR parent class to mux subclass
  */
 class mac_interface_mux_nr
 {
diff --git a/srsue/hdr/stack/mac_nr/proc_sr_nr.h b/srsue/hdr/stack/mac_nr/proc_sr_nr.h
index e88bc1165..1d0224350 100644
--- a/srsue/hdr/stack/mac_nr/proc_sr_nr.h
+++ b/srsue/hdr/stack/mac_nr/proc_sr_nr.h
@@ -13,7 +13,9 @@
 #ifndef SRSUE_PROC_SR_NR_H
 #define SRSUE_PROC_SR_NR_H
 
+#include "srsue/hdr/stack/mac_nr/mac_nr_interfaces.h"
 #include "srsran/interfaces/ue_mac_interfaces.h"
+#include "srsran/interfaces/ue_nr_interfaces.h"
 #include "srsran/srslog/srslog.h"
 #include <stdint.h>
 
@@ -23,14 +25,13 @@
 namespace srsue {
 
 class proc_ra_nr;
-class phy_interface_mac_nr;
 class rrc_interface_mac;
 
 class proc_sr_nr
 {
 public:
   explicit proc_sr_nr(srslog::basic_logger& logger);
-  int32_t init(proc_ra_nr* ra_, phy_interface_mac_nr* phy_, rrc_interface_mac* rrc_);
+  int32_t init(mac_interface_sr_nr* mac_, phy_interface_mac_nr* phy_, rrc_interface_mac* rrc_);
   void    step(uint32_t tti);
   int32_t set_config(const srsran::sr_cfg_nr_t& cfg);
   void    reset();
@@ -39,11 +40,11 @@ public:
 
 private:
   int  sr_counter    = 0;
-  bool is_pending_sr = 0;
+  bool is_pending_sr = false;
 
   srsran::sr_cfg_nr_t cfg = {};
 
-  proc_ra_nr*           ra  = nullptr;
+  mac_interface_sr_nr*  mac = nullptr;
   rrc_interface_mac*    rrc = nullptr;
   phy_interface_mac_nr* phy = nullptr;
   srslog::basic_logger& logger;
diff --git a/srsue/src/stack/mac_nr/mac_nr.cc b/srsue/src/stack/mac_nr/mac_nr.cc
index 18cea6d1f..f452eff67 100644
--- a/srsue/src/stack/mac_nr/mac_nr.cc
+++ b/srsue/src/stack/mac_nr/mac_nr.cc
@@ -47,7 +47,7 @@ int mac_nr::init(const mac_nr_args_t&  args_,
 
   // Init MAC sub procedures
   proc_ra.init(phy, &task_sched);
-  proc_sr.init(&proc_ra, phy, rrc);
+  proc_sr.init(this, phy, rrc);
 
   if (proc_bsr.init(&proc_sr, &mux, rlc, &task_sched) != SRSRAN_SUCCESS) {
     logger.error("Couldn't initialize BSR procedure.");
diff --git a/srsue/src/stack/mac_nr/proc_bsr_nr.cc b/srsue/src/stack/mac_nr/proc_bsr_nr.cc
index eb5dc3d8f..afb6aca56 100644
--- a/srsue/src/stack/mac_nr/proc_bsr_nr.cc
+++ b/srsue/src/stack/mac_nr/proc_bsr_nr.cc
@@ -114,7 +114,7 @@ void proc_bsr_nr::set_trigger(bsr_trigger_type_t new_trigger)
   // Trigger SR always when Regular BSR is triggered in the current TTI. Will be cancelled if a grant is received
   if (triggered_bsr_type == REGULAR) {
     logger.debug("BSR:   Triggering SR procedure");
-    // sr->start();
+    sr->start();
   }
 }
 
diff --git a/srsue/src/stack/mac_nr/proc_sr_nr.cc b/srsue/src/stack/mac_nr/proc_sr_nr.cc
index 7a1f8921f..23d0cef76 100644
--- a/srsue/src/stack/mac_nr/proc_sr_nr.cc
+++ b/srsue/src/stack/mac_nr/proc_sr_nr.cc
@@ -14,16 +14,15 @@
 #include "srsran/common/standard_streams.h"
 #include "srsran/interfaces/ue_phy_interfaces.h"
 #include "srsran/interfaces/ue_rrc_interfaces.h"
-#include "srsue/hdr/stack/mac_nr/proc_ra_nr.h"
 
 namespace srsue {
 
 proc_sr_nr::proc_sr_nr(srslog::basic_logger& logger) : logger(logger) {}
 
-int32_t proc_sr_nr::init(proc_ra_nr* ra_, phy_interface_mac_nr* phy_, rrc_interface_mac* rrc_)
+int32_t proc_sr_nr::init(mac_interface_sr_nr* mac_, phy_interface_mac_nr* phy_, rrc_interface_mac* rrc_)
 {
   rrc        = rrc_;
-  ra         = ra_;
+  mac        = mac_;
   phy        = phy_;
   initiated  = true;
   sr_counter = 0;
@@ -77,10 +76,10 @@ void proc_sr_nr::step(uint32_t tti)
   }
 
   // 1> if the MAC entity has no valid PUCCH resource configured for the pending SR:
-  if (!cfg.enabled || not phy->has_valid_sr_resource(0)) {
+  if (not phy->has_valid_sr_resource(cfg.item[0].sched_request_id)) {
     // 2> initiate a Random Access procedure (see clause 5.1) on the SpCell and cancel the pending SR.
     logger.info("SR:    PUCCH not configured. Starting RA procedure");
-    ra->start_by_mac();
+    mac->start_ra();
     reset();
     return;
   }
@@ -98,7 +97,7 @@ void proc_sr_nr::step(uint32_t tti)
     // 4> clear any PUSCH resources for semi-persistent CSI reporting;
     // ... TODO
 
-    ra->start_by_mac();
+    mac->start_ra();
     reset();
   }
 }
diff --git a/srsue/src/stack/mac_nr/test/CMakeLists.txt b/srsue/src/stack/mac_nr/test/CMakeLists.txt
index 3d4dd8f87..d9039c278 100644
--- a/srsue/src/stack/mac_nr/test/CMakeLists.txt
+++ b/srsue/src/stack/mac_nr/test/CMakeLists.txt
@@ -14,6 +14,10 @@ add_executable(proc_bsr_nr_test proc_bsr_nr_test.cc)
 target_link_libraries(proc_bsr_nr_test srsue_mac_nr srsran_common)
 add_test(proc_bsr_nr_test proc_bsr_nr_test)
 
+add_executable(proc_sr_nr_test proc_sr_nr_test.cc)
+target_link_libraries(proc_sr_nr_test srsue_mac_nr srsran_common)
+add_test(proc_sr_nr_test proc_sr_nr_test)
+
 add_executable(mac_nr_test mac_nr_test.cc)
 target_link_libraries(mac_nr_test srsue_mac_nr srsran_common)
 add_test(mac_nr_test mac_nr_test)
\ No newline at end of file
diff --git a/srsue/src/stack/mac_nr/test/proc_sr_nr_test.cc b/srsue/src/stack/mac_nr/test/proc_sr_nr_test.cc
new file mode 100644
index 000000000..666bce515
--- /dev/null
+++ b/srsue/src/stack/mac_nr/test/proc_sr_nr_test.cc
@@ -0,0 +1,104 @@
+/**
+ *
+ * \section COPYRIGHT
+ *
+ * Copyright 2013-2021 Software Radio Systems Limited
+ *
+ * By using this file, you agree to the terms and conditions set
+ * forth in the LICENSE file which can be found at the top level of
+ * the distribution.
+ *
+ */
+#include "srsran/common/buffer_pool.h"
+#include "srsran/common/common.h"
+#include "srsran/common/test_common.h"
+#include "srsue/hdr/stack/mac_nr/proc_sr_nr.h"
+#include "srsran/interfaces/ue_rrc_interfaces.h"
+
+using namespace srsue;
+
+class dummy_phy : public phy_interface_mac_nr
+{
+public:
+  dummy_phy() {}
+  void send_prach(const uint32_t prach_occasion_,
+                  const int      preamble_index_,
+                  const float    preamble_received_target_power_,
+                  const float    ta_base_sec_ = 0.0f) override
+  {
+    prach_occasion                 = prach_occasion_;
+    preamble_index                 = preamble_index_;
+    preamble_received_target_power = preamble_received_target_power_;
+  }
+  int tx_request(const tx_request_t& request) override { return 0; }
+  int set_ul_grant(std::array<uint8_t, SRSRAN_RAR_UL_GRANT_NBITS>, uint16_t rnti, srsran_rnti_type_t rnti_type) override
+  {
+    return 0;
+  }
+
+  void get_last_send_prach(uint32_t* prach_occasion_, uint32_t* preamble_index_, int* preamble_received_target_power_)
+  {
+    *prach_occasion_                 = prach_occasion;
+    *preamble_index_                 = preamble_index;
+    *preamble_received_target_power_ = preamble_received_target_power;
+  }
+  bool has_valid_sr_resource(uint32_t sr_id) override { return false; }
+  void clear_pending_grants() override {}
+
+private:
+  uint32_t prach_occasion                 = 0;
+  uint32_t preamble_index                 = 0;
+  int      preamble_received_target_power = 0;
+};
+
+class dummy_rrc : public rrc_interface_mac
+{
+  void ra_completed() {}
+  void ra_problem() {}
+  void release_pucch_srs() {}
+};
+
+class dummy_mac : public mac_interface_sr_nr
+{
+public:
+  void start_ra() { ra_started = true; }
+  bool check_ra_started() { return ra_started; }
+  void reset_ra_started() { ra_started = false; }
+
+private:
+  bool ra_started = false;
+};
+
+int proc_sr_basic_test()
+{
+  proc_sr_nr proc_sr_nr(srslog::fetch_basic_logger("MAC"));
+  dummy_rrc dummy_rrc; 
+  dummy_phy dummy_phy;
+  dummy_mac dummy_mac; 
+  
+  srsran::sr_cfg_nr_t cfg; 
+  cfg.enabled = true;  
+  cfg.num_items = 1; 
+  cfg.item[0].prohibit_timer = 0; 
+  cfg.item[0].sched_request_id = 0; 
+  cfg.item[0].trans_max = 64; 
+  proc_sr_nr.init(&dummy_mac, &dummy_phy, &dummy_rrc);
+  proc_sr_nr.set_config(cfg);
+  proc_sr_nr.start();
+
+  proc_sr_nr.step(0);
+  TESTASSERT(dummy_mac.check_ra_started() == true);
+
+  return SRSRAN_SUCCESS;
+}
+
+int main()
+{
+  srslog::init();
+
+  auto& mac_logger = srslog::fetch_basic_logger("MAC");
+  mac_logger.set_level(srslog::basic_levels::debug);
+  mac_logger.set_hex_dump_max_size(-1);
+  TESTASSERT(proc_sr_basic_test() == SRSRAN_SUCCESS);
+  return SRSRAN_SUCCESS;
+}
\ No newline at end of file