Former President Trump said Monday night that Vice President Kamala Harris' team told his campaign that she would not participate in a Fox News presidential debate on September 4.

The proposed debate would have been held in Pennsylvania and moderated by Fox News anchors Bret Baier and Martha MacCallum.

"I am not surprised by this development because I feel that she knows it is very difficult, at best, for her to defend her record setting Flip-Flopping on absolutely everything she once believed in, including her statements that THERE WILL BE NO FRACKING IN PENNSYLVANIA and her HORRIBLE Performance on the Border," Trump wrote on his social media platform Truth Social.

TRUMP, HARRIS SET FOR PRESIDENTIAL DEBATE ON ABC ON SEPTEMBER 10

Kamala Harris and Donald Trump

Former President Trump said Vice President Kamala Harris has declined to participate in a Fox News presidential debate on September 4. (Getty Images)

The former president had initially been reluctant to debate Harris after President Biden suspended his re-election campaign because she was not the Democratic Party's official candidate before later agreeing to debate her once she secured the party's nomination for president.

Trump and Harris have both confirmed they would participate in a Sept. 10 debate on ABC News. Trump previously said he also agreed to an NBC News debate on Sept. 25. 

The Harris campaign has said it would consider a second presidential debate in October. Both campaigns have also agreed to a vice presidential debate on CBS News on Oct. 1 between Minnesota Democratic Gov. Tim Walz and Ohio Republican Sen. J.D. Vance.

TRUMP AGREES TO DEBATE KAMALA HARRIS ON FOX NEWS

Trump

Trump and Harris have both confirmed they would participate in a Sept. 10 debate on ABC News. (Michael M. Santiago/Getty Images)

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"Voters deserve to see the candidates for the highest office in the land share their competing visions for our future," Harris' campaign communications director Michael Tyler said in a statement last week. "The more they play games, the more insecure and unserious Trump and Vance reveal themselves to be to the American people. Those games end now."

In place of the Fox News debate, Trump says he will participate in a town hall in Pennsylvania with Fox News host Sean Hannity.