(Bloomberg) -- Nikki Haley criticized Donald Trump’s populist stance toward NATO as well as his pledge to increase tariffs on China and other countries, attacking two of the central tenets of the former president’s argument for a return to the White House in 2024.

In an interview on Bloomberg Television’s Surveillance, Haley, Trump’s former UN Ambassador-turned-foe for the Republican presidential nomination, lambasted the GOP frontrunner for comments he made at a Saturday rally in her home state of South Carolina. Trump said he would leave European allies to fend for themselves against potential Russian aggression if they were delinquent on their NATO membership obligations.

“Do we want NATO to pay more? Of course we do. But the last thing we’re going to do is side with a thug. Keep in mind, Putin kills his opponents,” Haley said, referring to Russian President Vladimir Putin. “It is a mistake for Trump to side with Putin over our allies.”

She also called Trump’s second-term proposal to levy tariffs on China and other countries “ludicrous.”

The two are locked in an increasingly bitter contest for the nomination, with Haley as Trump’s last major GOP challenger. Trump has made his populist and more isolationist stance toward foreign and economic policy a key part of his platform, while Haley has espoused more traditional Republican policies, including a muscular US foreign policy role.

Trump on Saturday said NATO was “busted” until he forced members to “pay up.” He added that when a leader at an unspecified NATO meeting asked if the US would protect them if they were delinquent on spending, Trump responded that he would tell Russia to do “whatever the hell they want” to countries not meeting their commitments.

Trump doubled down on those comments Monday in a social media post saying that NATO countries must be asked to pay more.

“When I told the 20 Countries that weren’t paying their fair share that they had to PAY UP, and said without doing that you will not have U.S. Military Protection, the money came rolling in,” Trump said in the post. “After so many years of the United States picking up the tab, it was a beautiful sight to see. But now, without me there to say YOU MUST PAY, they are at it again.”

Trump’s comments sparked alarm in Washington and in world capitals, where leaders are already questioning the US commitment to global security with additional aid to Ukraine deadlocked in Congress by a domestic dispute over border security policy.

Read More: Trump’s Tirade Against NATO Remembered Differently By Europeans

Many Republicans, though, such as Senator Lindsey Graham of South Carolina, have sought to downplay Trump’s remarks.

“He’s not going to withdraw from NATO. The last thing Russia would do if Trump is president is start a war. He’s just trying to make a point,” Graham said.

Republican Senator Marco Rubio said he had “zero concern” about the remarks and that Trump was “telling a story” to make a point.

Asked about other Republicans defending Trump, Haley broke with them, saying the “goal is to make sure you communicate what’s right.”

Haley, who has been a vocal proponent of continued assistance to Kyiv, said the public should care about the fate of Ukraine, calling it a “pro-American, freedom-loving country” and warning that Putin was already threatening other countries.

“This is about preventing war. This is about keeping an alliance strong,” she added.

Trump’s remarks drew condemnation from President Joe Biden, who said the comments were “appalling and dangerous” in a statement issued by his reelection campaign. 

NATO Secretary-General Jens Stoltenberg, in a statement on Sunday, said the alliance remains “ready and able to defend all allies” and that he expected that “regardless of who wins the presidential election, the US will remain a strong and committed NATO ally.”

Tariffs on Imports

Haley also sharply criticized Trump’s support for across-the-board tariffs on imports — as well as a 60% levy on Chinese goods. 

“It is ludicrous that he wants to go and raise those tariffs to everything that we import,” Haley said on Surveillance. “That’s going to affect American families on anything from baby strollers to appliances. Every American family will see at least a $2,800 increase in their taxes.”

Trump has proposed a 60% tariff on all Chinese imports, an approach that would shrink a $575 billion trade pipeline to practically nothing, a Bloomberg Economics analysis shows. He’s also floated 10% across-the-board tariffs on all imports, an idea that has sparked concerns among European Union allies. 

Haley said China should be treated differently than other countries by ensuring the US is not economically dependent on Beijing to the point where it “could pull the rug out.”

Jason Miller, a Trump campaign spokesman, responded by casting Haley as soft on China. 

“Nikki Haley has called China a really great friend, gave away hundreds of acres of land in South Carolina to a company controlled by the CCP, and previously opposed President Trump’s tariffs on China,” Miller said, using an acronym for China’s Communist Party. “Of course Haley is going to continuing simping for China.”

Haley faces a tough path in the Feb. 24 South Carolina primary, where she trails Trump by over 30 percentage points, according to the RealClearPolitics polling average.

Trump is on the cusp of clinching the nomination after decisive wins in Iowa, New Hampshire and Nevada. A loss in the state where she was born and served two terms as governor would be a crippling blow to Haley’s campaign, although aides insist she will stay in the race through Super Tuesday on March 5, when more than a dozen states vote.

--With assistance from Annmarie Hordern, Jonathan Ferro and Lisa Abramowicz.

(Updates with Trump social media post in the seventh paragraph)

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