diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -24,6 +24,7 @@
 #include <util.h>
 #include <utilstrencodings.h>
 #include <validation.h>
+#include <validationinterface.h>
 #include <warnings.h>
 
 #include <boost/thread/thread.hpp> // boost::thread::interrupt
@@ -365,6 +366,21 @@
     return ret;
 }
 
+UniValue syncwithvalidationinterfacequeue(const Config &config,
+                                          const JSONRPCRequest &request) {
+    if (request.fHelp || request.params.size() > 0) {
+        throw std::runtime_error(
+            "syncwithvalidationinterfacequeue\n"
+            "\nWaits for the validation interface queue to catch up on "
+            "everything that was there when we entered this function.\n"
+            "\nExamples:\n" +
+            HelpExampleCli("syncwithvalidationinterfacequeue", "") +
+            HelpExampleRpc("syncwithvalidationinterfacequeue", ""));
+    }
+    SyncWithValidationInterfaceQueue();
+    return NullUniValue;
+}
+
 UniValue getdifficulty(const Config &config, const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 0) {
         throw std::runtime_error("getdifficulty\n"
@@ -1863,6 +1879,7 @@
     { "hidden",             "waitfornewblock",        waitfornewblock,        {"timeout"} },
     { "hidden",             "waitforblock",           waitforblock,           {"blockhash","timeout"} },
     { "hidden",             "waitforblockheight",     waitforblockheight,     {"height","timeout"} },
+    { "hidden",             "syncwithvalidationinterfacequeue", syncwithvalidationinterfacequeue, {} },
 };
 // clang-format on
 
diff --git a/test/functional/test_framework/util.py b/test/functional/test_framework/util.py
--- a/test/functional/test_framework/util.py
+++ b/test/functional/test_framework/util.py
@@ -446,7 +446,7 @@
     raise AssertionError("Chain sync failed: Best block hashes don't match")
 
 
-def sync_mempools(rpc_connections, *, wait=1, timeout=60):
+def sync_mempools(rpc_connections, *, wait=1, timeout=60, flush_scheduler=True):
     """
     Wait until everybody has the same transactions in their memory
     pools
@@ -458,6 +458,9 @@
             if set(rpc_connections[i].getrawmempool()) == pool:
                 num_match = num_match + 1
         if num_match == len(rpc_connections):
+            if flush_scheduler:
+                for r in rpc_connections:
+                    r.syncwithvalidationinterfacequeue()
             return
         time.sleep(wait)
         timeout -= wait