diff --git a/src/Stmt.h b/src/Stmt.h
index 53db73588d..dc1a33a45b 100644
--- a/src/Stmt.h
+++ b/src/Stmt.h
@@ -558,6 +558,9 @@ public:
 	// Optimization-related:
 	StmtPtr Duplicate() override;
 
+	bool IsReduced(Reducer* c) const override;
+	StmtPtr DoReduce(Reducer* c) override;
+
 private:
 	ExprPtr cond;
 	ExprPtr msg;
diff --git a/src/script_opt/Stmt.cc b/src/script_opt/Stmt.cc
index 02afbe7ae3..5ffdda0f28 100644
--- a/src/script_opt/Stmt.cc
+++ b/src/script_opt/Stmt.cc
@@ -924,6 +924,16 @@ StmtPtr AssertStmt::Duplicate()
 	return SetSucc(new AssertStmt(cond->Duplicate(), msg ? msg->Duplicate() : nullptr));
 	}
 
+bool AssertStmt::IsReduced(Reducer* c) const
+	{
+	return false;
+	}
+
+StmtPtr AssertStmt::DoReduce(Reducer* c)
+	{
+	return make_intrusive<NullStmt>();
+	}
+
 StmtPtr WhenStmt::Duplicate()
 	{
 	FuncType::CaptureList* cl_dup = nullptr;
diff --git a/testing/btest/Baseline/language.assert-hook/.stderr b/testing/btest/Baseline/language.assert-hook/.stderr
index 70a0f9c3a1..c04263e182 100644
--- a/testing/btest/Baseline/language.assert-hook/.stderr
+++ b/testing/btest/Baseline/language.assert-hook/.stderr
@@ -1,2 +1,2 @@
 ### BTest baseline data generated by btest-diff. Do not edit. Use "btest -U/-u" to update. Requires BTest >= 0.63.
-error in <...>/assert-hook.zeek, line 15: assertion failure: 1 != 1
+error in <...>/assert-hook.zeek, line 18: assertion failure: 1 != 1
diff --git a/testing/btest/Baseline/language.assert-hook/out b/testing/btest/Baseline/language.assert-hook/out
index f92c1a466f..f4efbf3732 100644
--- a/testing/btest/Baseline/language.assert-hook/out
+++ b/testing/btest/Baseline/language.assert-hook/out
@@ -1,2 +1,2 @@
 ### BTest baseline data generated by btest-diff. Do not edit. Use "btest -U/-u" to update. Requires BTest >= 0.63.
-assertion_failure, 1 != 1, , <...>/assert-hook.zeek, 15
+assertion_failure, 1 != 1, , <...>/assert-hook.zeek, 18
diff --git a/testing/btest/Baseline/language.assert-top-level/.stderr b/testing/btest/Baseline/language.assert-top-level/.stderr
index 18c84b3171..5322f47419 100644
--- a/testing/btest/Baseline/language.assert-top-level/.stderr
+++ b/testing/btest/Baseline/language.assert-top-level/.stderr
@@ -1,3 +1,3 @@
 ### BTest baseline data generated by btest-diff. Do not edit. Use "btest -U/-u" to update. Requires BTest >= 0.63.
-error in <...>/assert-top-level.zeek, line 5: assertion failure: getpid() == 0 (my pid greater 0? T)
+error in <...>/assert-top-level.zeek, line 7: assertion failure: getpid() == 0 (my pid greater 0? T)
 fatal error: failed to execute script statements at top-level scope
diff --git a/testing/btest/Baseline/language.assert/out b/testing/btest/Baseline/language.assert/out
index 256b93f1c8..886324ae99 100644
--- a/testing/btest/Baseline/language.assert/out
+++ b/testing/btest/Baseline/language.assert/out
@@ -1,3 +1,3 @@
 ### BTest baseline data generated by btest-diff. Do not edit. Use "btest -U/-u" to update. Requires BTest >= 0.63.
-error in <...>/assert.zeek, line 8: assertion failure: fmt("%s", 1) == "2"
+error in <...>/assert.zeek, line 11: assertion failure: fmt("%s", 1) == "2"
 fatal error: errors occurred while initializing
diff --git a/testing/btest/language/assert-hook.zeek b/testing/btest/language/assert-hook.zeek
index 1edca8ee6b..36909dec80 100644
--- a/testing/btest/language/assert-hook.zeek
+++ b/testing/btest/language/assert-hook.zeek
@@ -1,5 +1,8 @@
 # @TEST-DOC: Assert statement testing with assertion_failure and assertion_result implementation.
 #
+# Doesn't make sense for ZAM as it ignores assert's.
+# @TEST-REQUIRES: test "${ZEEK_ZAM}" != "1"
+#
 # @TEST-EXEC: zeek -b %INPUT >out
 # @TEST-EXEC: TEST_DIFF_CANONIFIER=$SCRIPTS/diff-remove-abspath btest-diff out
 # @TEST-EXEC: TEST_DIFF_CANONIFIER=$SCRIPTS/diff-remove-abspath btest-diff .stderr
diff --git a/testing/btest/language/assert-misc.zeek b/testing/btest/language/assert-misc.zeek
index 996ae3efd4..6c9de58432 100644
--- a/testing/btest/language/assert-misc.zeek
+++ b/testing/btest/language/assert-misc.zeek
@@ -1,5 +1,8 @@
 # @TEST-DOC: Test Describe() of assert statement. Expressions may be canonicalized.
 #
+# Doesn't make sense for ZAM as it ignores assert's.
+# @TEST-REQUIRES: test "${ZEEK_ZAM}" != "1"
+#
 # @TEST-EXEC: zeek -b %INPUT >out 2>&1
 # @TEST-EXEC: TEST_DIFF_CANONIFIER=$SCRIPTS/diff-remove-abspath btest-diff out
 
diff --git a/testing/btest/language/assert-top-level.zeek b/testing/btest/language/assert-top-level.zeek
index 738beca071..0bde1ad926 100644
--- a/testing/btest/language/assert-top-level.zeek
+++ b/testing/btest/language/assert-top-level.zeek
@@ -1,3 +1,5 @@
+# Doesn't make sense for ZAM as it ignores assert's.
+# @TEST-REQUIRES: test "${ZEEK_ZAM}" != "1"
 # @TEST-EXEC-FAIL: zeek -b %INPUT >out
 # @TEST-EXEC: TEST_DIFF_CANONIFIER=$SCRIPTS/diff-remove-abspath btest-diff .stderr
 
diff --git a/testing/btest/language/assert.zeek b/testing/btest/language/assert.zeek
index 9fdffeaeae..79ea8a9096 100644
--- a/testing/btest/language/assert.zeek
+++ b/testing/btest/language/assert.zeek
@@ -1,5 +1,8 @@
 # @TEST-DOC: Assert statement behavior testing without an assertion_failure() hook.
 #
+# Doesn't make sense for ZAM as it ignores assert's.
+# @TEST-REQUIRES: test "${ZEEK_ZAM}" != "1"
+#
 # @TEST-EXEC-FAIL: unset ZEEK_ALLOW_INIT_ERRORS; zeek -b %INPUT >out 2>&1
 # @TEST-EXEC: TEST_DIFF_CANONIFIER=$SCRIPTS/diff-remove-abspath btest-diff out