US President Joe Biden says he is ready to return to the campaign trail next week, but he faces a growing chorus of Democrats calling for him to step aside.

Mr Biden has been resting at his beach home in Delaware since contracting Covid, and the White House said on Saturday his symptoms “continue to improve steadily”.

But his time away from the spotlight has done nothing to diminish the focus on him, with Democrats churning over whether he should stay in the race for the White House, amid concerns over his general health following poor performances.

There is also party turmoil over whether his Vice-President Kamala Harris is next in line for the job or if a “mini-primary” should be quickly launched to choose a new nominee before the Democrat convention in August.

US vice-president Kamala Harris has led the Democrats’ campaign this week in Joe Biden’s absence (Erin Schaff/The New York Times/AP)

Ms Harris hit the campaign fundraising circuit on Saturday in Provincetown, Massachusetts, and picked up a nod from the state’s prominent Democratic senator Elizabeth Warren. She said before the visit that if Mr Biden was to step aside, his vice-president is “ready to step up”.

At the event, which organisers said raised 2 million US dollars (£1.5 million) and was attended by 1,000 guests, Ms Harris did not mention the calls for Mr Biden to leave the race or for her to replace him, instead repeating one of her regular campaign lines: “We’re going to win this election.”

To a cheering crowd, she added: “Do we believe in freedom? Do we believe in equality? Do we believe in the promise of America? Then are we ready to fight for it? When we fight, we win.”

Later as she boarded her plane to leave, Ms Harris flashed a thumbs-up after reporters asked how Mr Biden is doing as he recovers from Covid-19.

Installing Ms Harris at the top of the ticket, which would be a history-making moment for the party elevating the first woman, black person and person of South Asian descent as its presidential nominee, is not at all certain.

Nancy Pelosi is a key voice within the Democrats (Karl B DeBlaker/AP)

Officials from the highest ranks, including Speaker Emerita Nancy Pelosi, prefer an open process, some believing it would strengthen any Democratic nominee to confront Republican Donald Trump.

Speaking herself to a room full of North Carolina Democrats on Saturday, Ms Pelosi did little to quell speculation on Mr Biden’s path forward.

An event billed as the annual “Unity Dinner” came during a time of significant national discord within the Democrats.

Ms Pelosi gave a speech largely absent of mentions of Mr Biden’s presidential bid.

She spent most of her address recounting battles over budget and policy in the US House, highlighting the importance of funding public education and reiterating the dangers of the Republican agenda.

When she did mention Mr Biden, it was mostly to tout his administration’s policies.

At the end of her speech, Ms Pelosi shifted to discussing the party’s plans in the coming months and chose to focus on Democratic mobilisation efforts rather than who to mobilise behind.

“Are you ready for a Democratic president?” Ms Pelosi said amid cheers. “I thought so.”