Washington — House Speaker Mike Johnson called on Ukrainian President Volodymyr Zelenskyy to fire his ambassador to the U.S. amid the foreign leader’s escalating tension with former President Donald Trump and his allies. 

In a letter to Zelenskyy on Wednesday, Johnson demanded the immediate firing of Oksana Markarova, accusing her of interfering in the presidential election by organizing the Ukrainian president’s recent visit to an ammunition factory in Pennsylvania. 

“The facility was in a politically contested battleground state, was led by a top political surrogate for Kamala Harris, and failed to include a single Republican because — on purpose — no Republicans were invited,” the Louisiana Republican wrote. 

He called the visit a “partisan campaign event designed to help Democrats.” 

“This shortsighted and intentionally political move has caused Republicans to lose trust in Ambassador Markarova’s ability to fairly and effectively serve as a diplomat in this country,” he said. 

The Ukrainian Embassy and Pennsylvania governor’s office have not yet responded to a request for information about whether and Republican members of the congressional delegation were invited on the tour with Zelenskyy.

Zelenskyy is in the U.S. to address the United Nations General Assembly in New York, where he delivered remarks Wednesday. On Sunday, he toured an ammunition factory, thanking the employees who produce one of the most critically needed munitions for the war against Russia. 

The Republican-led House Oversight Committee is investigating the Pennsylvania trip to determine whether the Biden administration “attempted to use a foreign leader to benefit Vice President Harris’s presidential campaign.” Committee chairman, Rep. James Comer of Kentucky, cited the use of a U.S. Air Force jet to transport Zelenskyy to the battleground state, his meeting with Pennsylvania Gov. Josh Shapiro and Zelenskyy’s comments to the New Yorker. 

In a recent interview, Zelenskyy told the magazine that Trump “doesn’t really know how to stop the war even if he might think he knows how.” He also called Trump’s running mate, Sen. JD Vance of Ohio, “too radical.” 

Trump, for his part, has claimed that he would settle the Ukraine-Russia war as soon as he takes office, if he’s reelected in November. 

While campaigning in North Carolina on Wednesday, Trump knocked Zelenskyy for making “little nasty aspersions” toward him. 

“We continue to give billions of dollars to a man who refuses to make a deal,” he said of Zelenskyy. 

Despite the criticism, Trump confirmed Thursday afternoon he would meet with Zelenskyy on Friday morning at Trump Tower in New York City. Earlier in the day Trump had posted on social media a screenshot of an alleged message to him from Zelenskyy in which the Ukrainian leader asked to meet with Trump. 

“I believe it’s important for us to have a personal contact and to understand each other 100%,” the message said. 

Vance, who has opposed more aid to Ukraine, also criticized Zelenskyy at a rally in Michigan on Wednesday. 

“I don’t appreciate Zelenskyy coming to this country and telling the American taxpayers what they ought to do,” Vance said. “He ought to say thank you to the American taxpayers.” 

Zelenskyy was in Washington, D.C., on Thursday to meet with President Biden and Vice President Kamala Harris. He also had meetings with lawmakers on both sides of the aisle. Johnson did not attend Zelenskyy’s meeting with House members. 

Ukraine has pushed the U.S. and NATO to lift restrictions on its use of Western-supplied long-range missiles against targets in Russian territory. Russian President Vladimir Putin has said Kyiv’s use of long-range missiles to hit targets deep inside his country would represent a major escalation of NATO’s involvement in the war. 

Fin Gómez, Libby Cathey, Olivia Rinaldi and Taurean Small contributed to this report.

Caitlin Yilek

Caitlin Yilek is a politics reporter at CBSNews.com, based in Washington, D.C. She previously worked for the Washington Examiner and The Hill, and was a member of the 2022 Paul Miller Washington Reporting Fellowship with the National Press Foundation.