Harris backs debate to face off with Trump's VP pick

US Vice President Kamala Harris has accepted an invitation from CBS News to debate former president Donald Trump's vice presidential pick, the Biden campaign says as the Republican suggested he might wait until his party's convention in July to announce his selection.

Harris' team told the network she would debate in-studio on Tuesday, July 23, or Tuesday, August 13, and encouraged the Trump campaign to agree to one of the dates for his eventual vice presidential pick.

The Trump campaign did not immediately comment on the debate invitation.

Trump, in an interview with TMJ4 taped from New York, said there was "a pretty good chance" he would announce his vice presidential pick at the Republican convention in Milwaukee, which begins on July 15, rather than before.

"I don't say anything is 100 per cent but you're getting pretty close," he was quoted saying.

"I'll be doing it in Milwaukee. We're going to have a great time."

The announcement comes after President Joe Biden and Trump agreed to two debates to be hosted by CNN on June 27 and US broadcaster ABC on September 10.

The debates are not expected to take place before live audiences - a key demand of the Biden campaign that contributed to its decision to ditch the debates organised by the non-partisan Commission on Presidential Debates, which had organised every presidential and vice presidential general election debate since 1988.