Wednesday's debt-ceiling deal reassured global markets that the US will avert default, but also provided relief through backpay to workers furloughed in the government shutdown.

Some 800,000 government employees were forced off the job this month when Congress could not agree on a budget for the new fiscal year, which began October 1.

In some departments, like the Environmental Protection Agency, fully 95 percent of staff were deemed non-essential personnel and were effectively unemployed at the start of this month.

"Employees furloughed as a result of any lapse in appropriations which begins on or about October 1, 2013, shall be compensated at their standard rate of compensation, for the period of such lapse," according to the text of the deal provided by Senate Majority Leader Harry Reid's office.

Five days into the partial shutdown, the House of Representatives unanimously passed a bill guaranteeing retroactive pay for all federal employees, one of several efforts by the Republican-led chamber to chip away at the government shutdown piece by piece.

The White House had wholeheartedly backed the measure, although it stalled in the Senate.

But the chamber's leaders who crafted the compromise ultimately inserted it in the legislation.

The 35-page agreement, which funds government through January 15 and extends US borrowing authority through February 7, was cobbled together by a team of aides after days of intense negotiations between Reid and top Senate Republican Mitch McConnell.

It is expected to be approved by the Senate later Wednesday and then quickly sent across the US Capitol to the House, where leaders expect a vote the same night.

That would avert a potentially catastrophic scenario of the US government failing to pay its obligations, which could start to occur once the US Treasury reaches the debt ceiling on Thursday.