A top US congressional Democrat on Sunday accused US President Donald Trump and fellow Republicans of choosing to "weaponise hunger," as a prolonged government shutdown disrupts critical food benefits for millions of low-income Americans.

House Minority Leader Hakeem Jeffries warned that the Republican Party was "unserious" about reopening the government, which has remained shuttered for five weeks, delivering a multi-billion-US-dollar hit to the economy and leading to sharp accusations from both sides of the political aisle.

He accused Trump's Republicans – many of whom have stayed away from Washington for weeks as the Republican leadership keeps the House of Representatives idle – of manufacturing a crisis, including the lapse of funding for the Supplemental Nutrition Assistance Programme (Snap), which provides food aid to more than 42 million Americans.

"We want to reopen the government, we want to enact a bipartisan spending agreement that actually makes life better for everyday Americans," Jeffries told CNN's "State of the Union" talk show.

"It's very unfortunate that Donald Trump and Republicans have decided to weaponise hunger and withhold Snap benefits, even in contravention of two federal courts which have made clear that not a single person in this country should go without their nutritional assistance."

A federal judge recently ordered the government to use emergency funds to ensure the continuity of Snap. Trump expressed a willingness to comply but said he needed more clarification on how the administration could legally accomplish that.

Jeffries expressed his exasperation over suspending funding for Snap, which had operated uninterrupted for 60 years until now.

"Donald Trump and his administration (are) finding funding for other projects, but somehow they can't find money to make sure that Americans don't go hungry," he said.

Republicans have been seeking a straightforward extension of federal funding through a so-called short-term continuing resolution lasting until November 21, or beyond, to get the lights back on and prompt negotiations over a long-term solution.

But Democrats have baulked, demanding that any federal funding plan also include an extension of enhanced Obamacare health insurance subsidies, which are set to expire at year's end absent congressional action. (AFP)