World leaders who have sparred with the "America first" President Donald Trump greeted the rout of his Republican Party in the U.S. midterm elections with a measure of relief on Wednesday, allowing themselves to hope for a less combative U.S. foreign policy.

But that hope was seasoned with expectation that American voters' rebuke would not necessarily end the U.S. conflict with Iran or change Trump's policies on tariffs or his lukewarm-at-best support for Ukraine and America's European allies.

Progressive politicians cast the results as part of a trend of liberal comebacks around the world, following recent defeats for populists on the right in Hungary, Brazil and Serbia.