The US could experience a rare government shutdown this weekend, as a majority of senators appeared unwilling to back a new temporary spending bill.

Lawmakers in Washington DC have a midnight deadline to agree to the bill amid an ongoing delay in Republicans and Democrats reaching agreement on a longer-term spending bill.

A government shutdown sees many federal employees sent home (or 'furloughed') while others - including members of the military - may not be paid.

The most recent shutdown occurred in 2013 amid a bipartisan dispute over healthcare legislation. The shutdown lasted for 16 days.

In recent months, the two major US parties have been locked in a stalemate over a number of issues, including efforts to secure new protections for young undocumented immigrants known as 'Dreamers'.

Both houses have passed several shorter-term spending bills as efforts continued to reach a bipartisan deal.

While lawmakers in the House of Representatives last night passed another short-term bill in the hopes of averting a shutdown, a majority of Democratic and a small number of Republican senators have indicated they will not back the bill.

The Republicans have a narrow two-seat majority in the Senate, and need 60 votes to pass the short-term spending bill.

Republican Senator Jeff Flake said he was promised a vote on 'dreamer' - or DACA - legislation by the end of this month, but suggested that has been complicated by President Trump's uncertain stance on the issue.

In a statement, Senator Flake added that he was 'not inclined' to vote for another month-long spending bill, instead backing a suggestion by Democrats to extend the deadline by a few more days to try and find a bipartisan agreement to the outstanding issues.

"We won't be any better on the 16th of February as we will be next week," he argued.

My thoughts on DACA: "I maintain that the only way to find out what the president supports is to put a bill on the floor and vote on it." https://t.co/WzpoQOriGE

— Jeff Flake (@JeffFlake) January 19, 2018

Flake's colleague Lindsey Graham stated: "I am not going to support continuing this fiasco for 30 more days. It’s time Congress stop the cycle of dysfunction, grow up, and act consistent with the values of a great nation."

"We can’t keep kicking the can down the road"

The Washington Post reports that the bill that passed through the House includes an extension of a children's health insurance programme (CHIP) and delays to several unpopular health-care taxes - apparent efforts to persuade Democrats to back the temporary extension.

The Republican House Speaker Paul Ryan argued: "Senate Democrats are the only ones standing in the way of a fully funded government and a reauthorised health insurance program for children."

However, Senate minority leader Chuck Schumer claimed: "Democrats & Republicans have been negotiating for months across several issues. A bipartisan deal is within reach & now is the time to reach it. Now. Not a month from now.

"We have been skating by on continuing resolution after continuing resolution for almost six months [...] Now we are offered another month-long delay of the inevitable. We can’t keep kicking the can down the road."

The situation has been further complicated by the White House role in the negotiations.

Talks soured last week amid claims the president asked lawmakers - during a bipartisan meeting in the Oval Office - why "people from shithole countries" were arriving in the US. Those claims have been disputed.

This week, he has tweeted calling for funding for his controversial border wall with Mexico - border security being another apparent sticking point in the talks.

He has claimed a shutdown "will be devastating to our military", and appeared to undermine his own party's position with the suggestion that CHIP should be part of a long-term solution rather than a short-term one. 

Government Funding Bill past last night in the House of Representatives. Now Democrats are needed if it is to pass in the Senate - but they want illegal immigration and weak borders. Shutdown coming? We need more Republican victories in 2018!

— Donald J. Trump (@realDonaldTrump) January 19, 2018