Ukraine and key European leaders agreed Saturday to an unconditional 30-day ceasefire beginning May 12 with the backing of President Donald Trump, threatening Russian President Vladimir Putin with new "massive" sanctions if he failed to comply.

It’s a proposal that the Kremlin can neither reject nor accept, but one that may force it into an awkward choice, revealing Russian President Vladimir Putin’s true appetite for his brutal war of choice.

Leaders from four major European countries have threatened to ratchet up pressure on Russian President Vladimir Putin if he does not accept an unconditional 30-day ceasefire in Ukraine that they offered in a strong show of unity with Kyiv.