The US government has shut down much of its operations as deep partisan divisions prevented Congress and the White House from reaching a funding deal, setting off what could be a long, gruelling standoff that could lead to the loss of thousands of federal jobs.

There was no clear path out of the impasse, while agencies warned that the 15th government shutdown since 1981 would halt the release of a closely watched September employment report, slow air travel, suspend scientific research, withhold pay from US troops and lead to the furlough of 750,000 federal workers at a daily cost of $US400 million ($A600 million).

Trump, whose campaign to radically reshape the federal government is already on track to push out some 300,000 workers by December, warned congressional Democrats a shutdown c

See Full Page