ORLANDO, Florida—At the dawn of Russia’s new invasion of Ukraine this week, Donald Trump appeared to be on a Russian roadshow, telling whoever would listen about the wonder of President Vladimir Putin’s ability to take over the country next door on a whim.

But as Russia continues to attack Ukraine, several advisers and associates have practically begged the former president to end his effusive-sounding praise of Putin. Trump’s warm words for the Russian leader, who the ex-president regularly brags about knowing “very well,” has startled even some of Trump’s onetime lieutenants who were already conditioned to mask their disgust with the 45th U.S. president’s actions.