Weakened by the worst result for her party since 1949 and facing a more fractious political landscape at home, German Chancellor Angela Merkel could be forced to rein in plans to reshape Europe together with French President Emmanuel Macron.

Merkel's conservatives garnered more support than any other party in Sunday's German election, projections showed, ensuring that she will return for a fourth term as leader.

But her party appeared on track for its poorest performance since the first German election after World War II and its only path to power may be through an unwieldy, untested three-way coalition with the ecologist Greens and liberal Free Democrats (FDP), fierce critics of Macron's ideas for Europe.