It remains to be seen just how lasting and severe President Donald Trump’s turn against Vladimir Putin will be. Trump has criticized the Russian president in unprecedented terms in recent days and signaled he’ll send vital weapons to Ukraine.

But his frustration with Putin has grown. Last week, the president said the United States was taking “a lot of bullshit” from Putin. Today, he authorized a significant shipment of U.S. defensive weapons to Ukraine via NATO and threatened Russia with new tariffs if the war does not end in 50 days.

“Putin will not negotiate as a loser,” one of his longtime associates tells TIME by phone from Moscow. “He knows that winners don’t get punished, and if he wins, all of this” — the sanctions, the tariffs — “will go away.”

President Donald Trump issues Russian President Vladimir Putin a 50-day deadline to end Ukraine war or face 100% tariffs, prompting skepticism from the EU's chief diplomat and Kyiv's mayor over 50-day timeframe.

Melania Trump has highlighted Russia's continued attacks on Ukraine in private conversations, President Trump said on Monday.

Donald Trump has been growing increasingly angry with Putin ignoring his strict 50-day peace deal – with a senator warning what might come next for Russia if he doesn't step in line

Ivo Daalder, a senior fellow at Harvard Belfer Center, says that President Donald Trump realizes that he needs to change course because the Russian leader has been playing him "for years."

President Trump reveals how Russian leader 'talks nice, then bombs everybody' as the U.S. prepares to send Ukraine Patriot missiles under a NATO agreement.