diff --git a/src/backend/optimizer/path/joinpath.c b/src/backend/optimizer/path/joinpath.c
index 0344c5b10d917c186274afb3a66cb7b22d308d36..350b99ef178fd348fb8a222cb06be5ce08405ba5 100644
--- a/src/backend/optimizer/path/joinpath.c
+++ b/src/backend/optimizer/path/joinpath.c
@@ -110,9 +110,21 @@ add_paths_to_joinrel(PlannerInfo *root,
     Assert(innerrel->pathlist &&
            innerrel->cheapest_total_path);
 
-	/* Don't consider paths that have WorkTableScan as inner rel */
+	/*
+	 * Don't consider paths that have WorkTableScan as inner rel. If the outer
+	 * rel has a WorkTableScan as well, we won't be able to produce a usable
+	 * join so we need to error out.  This case can happen when to RECURSIVE
+	 * clauses are joined. RECURSIVE_CTE_FIXME: Revisit this when we gain
+	 * rescannable motions.
+	 */
 	if (innerrel->cheapest_startup_path && cdbpath_contains_wts(innerrel->cheapest_startup_path))
+	{
+		if (outerrel->cheapest_startup_path && cdbpath_contains_wts(outerrel->cheapest_startup_path))
+			ereport(ERROR,
+					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+					 errmsg("joining nested RECURSIVE clauses is not supported")));
 		return;
+	}
 	if (cdbpath_contains_wts(innerrel->cheapest_total_path))
 		return;
 
diff --git a/src/test/regress/expected/with_clause.out b/src/test/regress/expected/with_clause.out
index 1493c3914034596782bef33cad6b1679aedb1eaa..3f7c8a9c17fbc9d41d360b9597a410653ea92b30 100644
--- a/src/test/regress/expected/with_clause.out
+++ b/src/test/regress/expected/with_clause.out
@@ -2163,3 +2163,21 @@ SELECT * FROM y;
  1100 |  
 (15 rows)
 
+-- Nested RECURSIVE queries with double self-referential joins are planned by
+-- joining two WorkTableScans, which GPDB cannot do yet. Ensure that we error
+-- out with a descriptive message.
+SET gp_recursive_cte TO ON;
+WITH RECURSIVE r1 AS (
+	SELECT 1 AS a
+	UNION ALL
+	(
+		WITH RECURSIVE r2 AS (
+			SELECT 2 AS b
+			UNION ALL
+			SELECT b FROM r1, r2
+		)
+		SELECT b FROM r2
+	)
+)
+SELECT * FROM r1 LIMIT 1;
+ERROR:  joining nested RECURSIVE clauses is not supported
diff --git a/src/test/regress/expected/with_clause_optimizer.out b/src/test/regress/expected/with_clause_optimizer.out
index c4ec3345c4a96d7002b46e0923846c9a31e9355a..56c3ed909c2dda53f49cc62f8220a14024399519 100644
--- a/src/test/regress/expected/with_clause_optimizer.out
+++ b/src/test/regress/expected/with_clause_optimizer.out
@@ -2162,3 +2162,21 @@ SELECT * FROM y;
  1100 |  
 (15 rows)
 
+-- Nested RECURSIVE queries with double self-referential joins are planned by
+-- joining two WorkTableScans, which GPDB cannot do yet. Ensure that we error
+-- out with a descriptive message.
+SET gp_recursive_cte TO ON;
+WITH RECURSIVE r1 AS (
+	SELECT 1 AS a
+	UNION ALL
+	(
+		WITH RECURSIVE r2 AS (
+			SELECT 2 AS b
+			UNION ALL
+			SELECT b FROM r1, r2
+		)
+		SELECT b FROM r2
+	)
+)
+SELECT * FROM r1 LIMIT 1;
+ERROR:  joining nested RECURSIVE clauses is not supported
diff --git a/src/test/regress/sql/with_clause.sql b/src/test/regress/sql/with_clause.sql
index 03176e270b8ee6f966e829ca22067fe7f46567bd..78b007a9bce86099c9ba4bd1c0a3666e8d554de1 100644
--- a/src/test/regress/sql/with_clause.sql
+++ b/src/test/regress/sql/with_clause.sql
@@ -341,3 +341,21 @@ WITH t AS (
 SELECT m BETWEEN 100 AND 1500 FROM t LIMIT 1;
 
 SELECT * FROM y;
+
+-- Nested RECURSIVE queries with double self-referential joins are planned by
+-- joining two WorkTableScans, which GPDB cannot do yet. Ensure that we error
+-- out with a descriptive message.
+SET gp_recursive_cte TO ON;
+WITH RECURSIVE r1 AS (
+	SELECT 1 AS a
+	UNION ALL
+	(
+		WITH RECURSIVE r2 AS (
+			SELECT 2 AS b
+			UNION ALL
+			SELECT b FROM r1, r2
+		)
+		SELECT b FROM r2
+	)
+)
+SELECT * FROM r1 LIMIT 1;