White House National Security Adviser Mike Waltz said Sunday that Ukrainian President Volodymyr Zelenskyy blew a chance to advance peace talks after he left the White House without signing a minerals deal — warning that the patience of the American taxpayer is “not unlimited.”

Mr. Waltz said the dustup between President Trump and Mr. Zelenskyy at the White House raised questions as to whether the Ukrainian president is “ready to negotiate in good faith towards” the war that started when Russia invaded Ukraine three years ago.

“This was a huge missed opportunity for him and for his country,” Mr. Waltz said on CNN’s “State of the Union.”

Mr. Waltz said momentum had been building behind the peace talks before Mr. Zelenskyy left the turbulent White House meeting Friday without signing a minerals deal, which Mr. Trump said is a way for Ukraine to repay the United States for its financial aid and weaponry.

“We were ready to sign this deal,” Mr. Waltz said. “It is unclear whether President Zelenskyy — particularly after what we saw Friday — is ready to transition Ukraine to an end to this war, and to negotiate and to have to compromise,” Mr. Waltz said.

He said Mr. Trump has made it clear Russia and Ukraine will have to compromise, including on territory and security guarantees.

The reaction to the explosive exchange at the White House has primarily split along partisan lines.

After the meeting, Sen. Lindsay Graham raised doubts whether the U.S. can continue to work with Mr. Zelenskyy. The South Carolina Republican said the Ukrainian leader “either needs to resign or send somebody over that we can do business with, or he needs to change.”

Asked whether Mr. Zelenskyy should step down, Mr. Waltz said the Trump administration is looking to work with a “leader that can deal with us, eventually deal with the Russians, and end this war.”

“If it becomes apparent that President Zelenskyy’s either personal motivations or political motivations are divergent from ending the fighting in his country than I think we have a real issue on our hands,” he said. “The patience of the American people to keep giving billions and billions and billions with no end in sight is not unlimited.”

Mr. Waltz also said the U.S. would not support Ukraine’s joining NATO.

“One thing is clear: We do not see Ukraine being a member of NATO because that would automatically drag U.S. troops in,” he said.

• Seth McLaughlin can be reached at smclaughlin@washingtontimes.com.