Sensing that President Donald Trump much prefers tough rhetoric to tough action, Russian President Vladimir Putin is testing Trump’s willingness to force him to make hard concessions for peace.

Following a meeting with Ukrainian President Volodymyr Zelensky and Trump at the Vatican on Saturday, Trump complained publicly about recent high-intensity Russian air strikes on Ukrainian civilian targets. He then expressed frustration that Putin “might just be tapping me along,” asking whether he “has to be dealt with differently, through ‘Banking’ or ‘Secondary Sanctions?’” In response, Putin announced a three-day ceasefire by Russian forces in Ukraine from May 8 through May 10, timed to celebrate the May 8, 1945, Allied victory over Nazi Germany.