CNN
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President-elect Donald Trump has selected Matthew Whitaker, who served as acting attorney general during Trump’s first term, as his pick for U.S. ambassador to NATO.

“Matt is a strong fighter and loyal patriot who will ensure that the interests of the United States are advanced and defended,” Trump said in a press release on Wednesday. “Matt will strengthen relations with our NATO allies and remain steadfast in the face of threats to peace and stability. He will put AMERICA FIRST.”

If confirmed, Whitaker will lead the U.S. mission to NATO at a time when the defensive alliance may still face one of its toughest challenges: how to continue supporting Ukraine in its war against Russia. He will also likely be tasked with increasing pressure on countries in the alliance to increase their defense spending — renewing an effort Trump made during his first term.

Earlier this year, NATO announced it would set up a mission to coordinate the delivery of military equipment and training for Ukraine – an effort largely led by the US – in a move that some saw as an attempt to boost support’ Trump-proof. Trump and newly elected Vice President JD Vance have expressed doubts about the extent to which the US remains committed to Kiev, as the war continues more than two and a half years after the invasion of Russian forces.

During the campaign, Trump also indicated that he would only adhere to NATO’s mutual defense obligations for countries that contribute enough of their annual budgets to defense. He said during the campaign that “one of the presidents of a great country” asked him at one point whether the U.S. would still defend the country if invaded by Russia even if “they don’t pay.”

“No, I wouldn’t protect you,” Trump recalled telling that president. ‘Actually, I would encourage them to do whatever they want. You have to pay. You have to pay your bills.”

In his remarks earlier this month in Paris, NATO Secretary General Mark Rutte called for “more robust transatlantic defense cooperation and increased defense investments.”

“We must stand together – Europe, North America and our global partners – to keep our people safe and prosperous,” he said.

Whitaker, a loyal Trump ally, has no foreign policy background. He was a former acting attorney general during Trump’s first term and temporarily led the Justice Department after Trump fired Jeff Sessions.

Trump grew frustrated with Sessions because the then-attorney general recused himself from all matters related to the 2016 campaign, including special counsel Robert Mueller’s investigation into Russian election interference. Whitaker, on the other hand, was openly critical of the Russia investigation.

During a brief tenure at the top of the Justice Department, Whitaker quickly took control of Mueller from Deputy Attorney General Rod Rosenstein. Although Whitaker did not recuse himself like his predecessor, he repeatedly said he had not discussed the investigation with Trump.

He sparred with Democratic lawmakers who argued his nomination was unconstitutional. He also clashed with Democrats during congressional testimony, often refusing to answer their questions.

Before becoming acting attorney general, Whitaker was the U.S. attorney for the Southern District of Iowa and chief of staff to Sessions.