diff --git a/src/txmempool.cpp b/src/txmempool.cpp
index f38290fb77..49073b95ba 100644
--- a/src/txmempool.cpp
+++ b/src/txmempool.cpp
@@ -793,7 +793,7 @@ void CTxMemPool::removeForReorg(const CCoinsViewCache *pcoins, unsigned int nMem
 void CTxMemPool::removeConflicts(const CTransaction &tx)
 {
     // Remove transactions which depend on inputs of tx, recursively
-    LOCK(cs);
+    AssertLockHeld(cs);
     for (const CTxIn &txin : tx.vin) {
         auto it = mapNextTx.find(txin.prevout);
         if (it != mapNextTx.end()) {
diff --git a/src/txmempool.h b/src/txmempool.h
index 683bd388f7..c88b7ade34 100644
--- a/src/txmempool.h
+++ b/src/txmempool.h
@@ -576,7 +576,7 @@ public:
 
     void removeRecursive(const CTransaction &tx, MemPoolRemovalReason reason = MemPoolRemovalReason::UNKNOWN);
     void removeForReorg(const CCoinsViewCache *pcoins, unsigned int nMemPoolHeight, int flags);
-    void removeConflicts(const CTransaction &tx);
+    void removeConflicts(const CTransaction &tx) EXCLUSIVE_LOCKS_REQUIRED(cs);
     void removeProTxPubKeyConflicts(const CTransaction &tx, const CKeyID &keyId);
     void removeProTxPubKeyConflicts(const CTransaction &tx, const CBLSPublicKey &pubKey);
     void removeProTxCollateralConflicts(const CTransaction &tx, const COutPoint &collateralOutpoint);