NEW YORK (AP) — President Joe Biden said Friday that he is willing to debate his presumptive Republican opponent, Donald Trump, later this fall – his most definitive comment yet on the issue.

Trump said he was ready, though he questioned Bidens’s willingness.

Biden’s comment came during an interview with the Sirius XM radio host Howard Stern, who asked him whether he would participate in debates against Trump.

“I am, somewhere. I don’t know when,” Biden said. “But I’m happy to debate him.”

Until now, Biden’s reelection campaign had declined to commit to participating in the debates, a hallmark of every general election presidential campaign since 1976.

Biden himself had also been vague, saying in March that whether he debated Trump “depends on his behavior.” The two men debated twice during the 2020 general election — a campaign year constrained significantly by COVID-19 restrictions — and Biden was notably irritated by Trump’s antics in the chaotic first debate that year.

“Will you shut up?” Biden told Trump at one point during the first debate.

Trump campaign officials have said for some time that the former president is prepared to debate Biden anytime, and Chris LaCivita, Trump campaign senior adviser, quickly responded to Biden’s remarks on the social media site X: “OK let’s set it up!”

Later Friday, Trump reacted to Biden’s new public willingness to debate by saying “everyone knows he doesn’t really mean it” but suggested either next Monday evening, Tuesday evening or Wednesday evening, when Trump will be campaigning in Michigan. The former president is suggesting evenings because he is otherwise attending proceedings for his hush money criminal trial in New York.

Trump is required to be in court every day but Wednesdays. In a statement on his own social media platform, Trump also challenged Biden to debate at the Manhattan courthouse on Friday night, since both men were in New York at the same time. Biden has since returned to Washington.

Yet Friday is also Melania Trump’s birthday, and the former president had already said earlier in the day that he was flying back to Florida to spend the day with his wife.