diff --git a/src/common/backend/parser/gram.y b/src/common/backend/parser/gram.y
index ac0d6f62e..4ab1c60a5 100644
--- a/src/common/backend/parser/gram.y
+++ b/src/common/backend/parser/gram.y
@@ -19064,6 +19064,15 @@ TransactionStmt:
 				}
 			| START TRANSACTION WITH CONSISTENT SNAPSHOT
 				{
+					if (!DB_IS_CMPT(B_FORMAT)) {
+						const char* message = "WITH CONSISTENT SNAPSHOT is supported only in B-format database.";
+						InsertErrorMessage(message, u_sess->plsql_cxt.plpgsql_yylloc);
+						ereport(errstate,
+							(errmodule(MOD_PARSER),
+								errcode(ERRCODE_SYNTAX_ERROR),
+								errmsg("WITH CONSISTENT SNAPSHOT is supported only in B-format database."),
+								parser_errposition(@3)));
+					}
 					TransactionStmt *n = makeNode(TransactionStmt);
 					n->kind = TRANS_STMT_START;
 					n->options = NIL;
diff --git a/src/test/regress/input/transaction_with_snapshot.source b/src/test/regress/input/transaction_with_snapshot.source
index 9047bb74c..f23796eb7 100644
--- a/src/test/regress/input/transaction_with_snapshot.source
+++ b/src/test/regress/input/transaction_with_snapshot.source
@@ -1,3 +1,5 @@
+\c regression
+start transaction with consistent snapshot;
 create database with_snapshot_test dbcompatibility 'b';
 \c with_snapshot_test;
 set global transaction isolation level repeatable read;
diff --git a/src/test/regress/output/transaction_with_snapshot.source b/src/test/regress/output/transaction_with_snapshot.source
index d7fdf2498..4c9c48a61 100644
--- a/src/test/regress/output/transaction_with_snapshot.source
+++ b/src/test/regress/output/transaction_with_snapshot.source
@@ -1,3 +1,8 @@
+\c regression
+start transaction with consistent snapshot;
+ERROR:  WITH CONSISTENT SNAPSHOT is supported only in B-format database.
+LINE 1: start transaction with consistent snapshot;
+                          ^
 create database with_snapshot_test dbcompatibility 'b';
 \c with_snapshot_test;
 set global transaction isolation level repeatable read;