Hopes for a quick agreement on a proposed stimulus bill worth up to $2trn to help cope with the coronavirus pandemic took a blow when a top Democrat left talks saying she would come up with her own plan.

Nancy Pelosi, the House speaker who had flown in to DC from San Francisco, told reporters: "From my standpoint, we're apart."

Her comments dented hopes for a bipartisan deal being agreed as early as Monday – although with the top Democrat in the Senate, Chuck Schumer, making more positive noises, an agreement was not off the table.

Mr Schumer said: "We're continuing to talk."

The $2trn package aims to shore up the US economy as the coronavirus sees millions of employees and businesses in doubt about their future, with thousands of workers already having lost their jobs.

Democrats say they had preliminary agreements on providing an extra $200bn to hospitals and first responders, establishing an extension on unemployment insurance, making sure renters are not evicted and protections for students paying back loans.

But Democratic senator Tammy Duckworth told CNN that at 8pm on Saturday the Republican Senate leader, Mitch McConnell, pulled negotiators out of talks.

He reportedly said he was going to draft a "final legislative text" without the involvement of Democrats.

Ms Duckworth accused the Treasury secretary Steven Mnuchin, who is involved in the talks, of trying to set up a $500bn slush fund for the benefit of business, allowing them to ignore restrictions on using federal funds for stock buybacks and on allowing executives to increase their wages.

Republicans insist they have made a series of compromises to take in Democratic demands.

The proposed stimulus package – which could provide $1,200 to most American taxpayers – would be the third passed by Congress to try to stem the effects of the coronavirus pandemic.

An $8.3m package aimed at supporting the medical response to Covid-19 was followed by a $100bn deal, the Families First Coronavirus Response Act, which expanded unemployment benefits and Medicare and provided for paid sick leave, childcare leave and free testing for Covid-19.