US in state of shut-down after budget row

The Republican-led House of Representatives insisted on delaying President Obama's healthcare reform, Obamacare, as a condition for passing a bill.

More than 800,000 federal employees face unpaid leave with no guarantee of back pay once the deadlock is over.

It is the first partial shutdown in 17 years.

The economic impact will depend on how long the deadlock lasts, but it is estimated that a three-week shutdown could shave as much as 0.9% from US GDP this quarter.

With less than one hour to go before midnight, the Republican-led House called for a conference - a bipartisan committee with the Senate - to try to thrash out a deal, but Democrats said it was too late to avoid a shutdown.

The White House's budget office began notifying federal agencies to begin an "orderly shutdown" as midnight approached.

One of the first casualties of the shutdown was the Twitter account for the US Capitol.

"Due to a lapse in government funding, this account will not be active until further notice," it posted.

Earlier it had warned that the Capitol's visitors' centre would be closed if the shutdown went ahead, and all tours would be suspended.

Shortly after midnight, President Obama tweeted: "They actually did it. A group of Republicans in the House just forced a government shutdown over Obamacare instead of passing a real budget."

House Speaker John Boehner told reporters he hoped the Senate would accept an offer of conference with the House "so we can resolve this for the American people".

"The House has voted to keep the government open but we also want basic fairness for all Americans under Obamacare," he said.

The Senate is to meet again on Tuesday, Democratic Senate Majority Leader Harry Reid said.