By Andy Sullivan,David Morgan,Richard Cowan

Copyright theage

At midnight on Tuesday (2pm Wednesday AEST), the US will enter its 15th government shutdown since 1981 – the first in almost seven years – unless Republicans and Democrats in Congress agree on a deal to temporarily fund federal agencies with the start of a new fiscal year.

No signs pointed to such an outcome, however. Any last-minute agreement would also have to be approved by the Republican-controlled House, which is not due to convene until Wednesday, after funding expires.

The Republican-controlled Senate is expected to vote on a temporary spending bill that has failed once already, with no sign that a second vote will bring success before the midnight deadline.

Democrats want to modify the bill to extend health benefits for millions of Americans that are due to expire at the end of the year. Republicans say they must tackle that issue separately.