US President Joe Biden is hoping a televised interview on Friday will steady his imperiled reelection bid -- but a repeat of his disastrous debate performance could be his downfall.

In the week since his debate against Donald Trump -- their first head-to-head of the 2024 election cycle -- 81-year-old Biden has failed to quell panic among his Democratic Party.

For 90 minutes last Thursday, a raspy Biden struggled to express himself clearly, stumbling over words and losing his train of thought.

A growing chorus in his party has since called for him to prove he has the energy to defeat Trump in November, and handle another four years in the White House.

Despite winning the backing of Democratic governors, who met with him at an emergency meeting on Wednesday, at least three of his party members in Congress have called on him to step aside, as have several major newspaper editorial boards and a raft of political commentators.

The president has said that he is "not leaving" and is "in this race to the end," but post-debate polls have shown Trump's narrow lead widening.

Biden has also not yet spoken publicly without a teleprompter since the debate, other than some brief remarks.

So Friday's interview with ABC presenter George Stephanopoulos, set to be recorded during a campaign trip to Wisconsin, will be a key moment for Biden to dispel the worries and reset expectations.

With soaring anticipation for the interview, ABC has switched up its original plan of airing excerpts through the weekend, and will instead broadcast it in full Friday at 8:00 pm (0000 GMT Saturday).

 

- 'Essential' interview -

Biden will face a journalist who knows the workings of political communication like no one else.

Stephanopoulos worked for former Democratic president Bill Clinton during his first campaign and was one of his closest advisors during his first term in the White House.

Biden, a former stutterer, will also have to win back confidence with clear and cohesive speech, as much as on substance.

Former House speaker Nancy Pelosi, one of the most influential Democratic voices, has deemed it "essential" that the president do one or even two high-profile interviews.

Other supporters have called for a long-form news conference to judge his stamina.

The White House has announced that he will hold a news conference during the NATO summit in Washington next week, but has not revealed any details on its format or length.

Trump has meanwhile dared Biden to another debate, or an "all-on discussion," saying on Thursday that he was ready "anytime, anywhere, any place."

With speculation still swirling over a potential switch-up at the top of the Democratic ticket, Kamala Harris, the nation's first female vice president, has suddenly been forced into the spotlight.

The 59-year-old former California prosecutor -- who joined Biden at Thursday's July 4 celebrations -- has been performing a delicate balancing act since the debate.

She has offered unwavering support for Biden in public but is standing by as a leading contender to replace him if he steps aside.