Sen. JD Vance, former President Donald Trump s running mate, wont debate Vice President Kamala Harris ahead of the Democratic National Convention next month, the Trump campaign said Wednesday, citing uncertainty about who the Democratic candidate will be.

While Trump officially announced Vance as his VP pick earlier this week, calling him the best suited person for the role, growing pressure on President Joe Biden to step down from the race following his poor performance at the CNN debate in late June has led to questions about whether Harris could replace him at the top of the Democratic ticket.

Democrats will officially nominate their candidates by the end of their party convention scheduled for Aug. 19-22.

We dont know who the Democrat nominee for Vice President is going to be, so we cant lock in a date before their convention, Brian Hughes, a senior adviser for the Trump campaign, said in a statement on the VP debate.

To do so would be unfair to Gavin Newsom, JB Pritzker, Gretchen Whitmer, or whoever Kamala Harris picks as her running mate, Hughes added, referring to popular Democratic governors who have been floated as potential candidates on the partys ticket should Biden drop out.

In a call Tuesday after Vances nomination, Harris and the Ohio senator reportedly said they looked forward to debating each other, but did not get drawn into more details.

President Joe Bidens reelection campaign on Wednesday said Harris has accepted dates put forward by CBS News for a vice presidential debate, including the latest offer for Aug. 12. The Trump campaign has not officially agreed to take part in the CBS event.

The Trump team had committed to a Fox News vice presidential debate earlier this year, ahead of Vances selection, but no date has been set for that faceoff.

Meanwhile, Vance is under scrutiny for his extreme positions, including his past comments that he would certainly like for abortion to be illegal nationally in a 2022 episode of the podcast Very Fine People, which was resurfaced by CNN.

Bidens campaign suggested the revelations are responsible for Vance not committing to debate Harris.

Now suddenly right after a damning new leak showing his support for a nationwide abortion ban, Vance is backing off a debate against Vice President Harris, who has spent the last two years prosecuting the case on behalf of reproductive freedom, the campaign said.

This debate has been discussed for two months now. If JD Vance is unwilling to defend the Trump-Vance record on the debate stage, he should just say so, it continued.

Biden, who tested positive for COVID-19 Wednesday, is reportedly becoming more receptive to the idea of dropping out, a senior Democratic adviser told CNN , despite his public statements that he isnt entertaining the possibility while more senior members of his party are publicly and privately calling on him to reconsider his decision to run for reelection. This comes as top donors for the Biden campaign are allegedly beginning to rethink their support .

In an interview with BETs Ed Gordon, Biden said he would consider dropping out of the presidential race if a medical condition emerged.