U.S. President Donald Trump has privately expressed doubts about his ability to influence Vladimir Putin after Russia rebuffed U.S. calls for a Ukraine ceasefire, according to Axios. Trump admitted to aides that he underestimated Putin’s resolve and desire for peace, with sources noting growing concern over his lack of leverage to end the war. Despite Trump’s threats of serious consequences, Putin has not agreed to a truce or met with Ukraine’s President Zelenskyy, leaving Trump’s Ukraine strategy under scrutiny. The White House has not enacted new sanctions since Russia defied warnings; instead, Trump called on European allies to ramp up pressure on Moscow and China.