US Vice-President J.D. Vance on Sunday said there will be deeper cuts to the federal workforce the longer the government shutdown goes on, adding to the uncertainty facing hundreds of thousands who are already furloughed without pay amid the stubborn stalemate in Congress.

Vance warned that as the federal shutdown entered its 12th day, the new cuts would be “painful”, even as he said the Trump administration worked to ensure the military is paid this week and some services would be preserved for low-income Americans, including food help.

Still, hundreds of thousands of government workers have been furloughed in recent days and, in a court filing on Friday, the Office of Management and Budget said well over 4,000 federal employees would soon be fired in conjunction with the shutdown.

The effects of the shutdown also grew on Sunday with the Smithsonian announcing its museums, research centres and the National Zoo are temporarily closed going forward for lack of funding.

“To be clear, some of these cuts are going to be painful. This is not a situation that we relish. This is not something that we’re looking forward to, but the Democrats have dealt us a pretty difficult set of cards.”