Bahrain's main opposition groups have eased their conditions for talks to end a crisis that has drawn in neighbouring Gulf armies, a Reuters report said.

The groups led by Bahrain's largest opposition party, Wefaq, in a statement late on Saturday called on security forces to free all those detained, end their crackdown and ask Gulf troops to leave so talks could begin.

"Prepare a healthy atmosphere for the start of political dialogue between the opposition and the government on a basis that can put our country on the track to real democracy and away from the abyss," it said.

The group retreated from much more ambitious conditions for talks it set last week, including the creation of a new government not dominated by royals and the establishment of a special elected council to redraft Bahrain's constitution.

The new conditions, which also include ending sectarian rhetoric and removing forces who have surrounded a major hospital in recent days, would bring the political process back to the position it was in before the uprising began a month ago.

Bahraini police and troops moved on Wednesday to end weeks of protests that prompted the king to declare martial law and drew in troops from Bahrain's neighbours.   

Sunday was the first working day after a week that saw closures of schools and universities to prevent outbreaks of sectarian clashes that had become virtually a daily event.

In an effort to bring life back to normal, Bahrain's military rulers cut back by four hours on Saturday a 12 hour curfew that had been imposed on large areas of Manama.    

The curfew now runs from 8 pm to 4 am from the Seef Mall area in Manama, through the Pearl roundabout and the financial district to the diplomatic area.

Bahrain urged employees working in the public sector and both public and private sector schools and universities to return to work after days of closures and shortened hours.   

State television also aimed to show viewers the island kingdom had returned to normalcy, airing soap operas, documentaries and montages of expatriates expressing relief at their regained sense of security in Bahrain.   

Some of the larger malls have begun to reopen after days of closures and there were fewer checkpoints in the streets. - Reuters