People wearing masks pass by a store closing soon in Santa Monica, California, on Tuesday, amid the coronavirus pandemic. Photo: AFP

Democrats and Republicans in the US Congress late Tuesday were far from reaching an agreement on a new package to support the world's largest economy, brought to its knees by the virus pandemic.

"Very sadly, after months of deadly delay, the Republicans have unveiled a proposal that would only prolong the suffering for millions of workers and families across America," House Speaker Nancy Pelosi wrote in letter to her fellow Democrats, following two rounds of negotiations with the White House and Republican lawmakers.

In the Senate, Republican majority leader Mitch McConnell defended his party's proposal, unveiled on ­Monday, that calls for $1 trillion in stimulus aid.

Back in May, the House Democrats unveiled a $3 trillion coronavirus response package, the largest yet, to fund efforts to fight the pandemic and provide emergency payments to millions of Americans.

With only 100 days to go before the US presidential election, talks are tense between the parties - but also among Republicans, some of whom are refusing to spend much and are even criticizing the White House.

Stumbling blocks to reaching an agreement include extending aid to the millions left jobless by the pandemic. Under the Republican plan, unemployment payments would drop to $200 a week, compared to $600 per week under the current plan - set to expire at the end of July.

Some lawmakers are asking to simply extend these payments until the end of the week to give negotiators time to reach a deal on the larger stimulus package.