Emergency legislation to enable the Northern Ireland Assembly to be recalled on 15 May has been published by the government.
The NI Assembly has been suspended since October 2002
It imposes an "immovable deadline" of 24 November in place for forming a power-sharing executive.
The government also confirmed the next assembly elections would be postponed until May 2008 if the executive is restored by this date.
The legislation is expected to become law by 8 May.
Failure to elect a first and deputy first minister by the November deadline would mean that assembly member's pay would end the following day.
The assembly would then be dissolved in May next year, or earlier if the secretary of state decides.
Speaking on Thursday, Northern Ireland Secretary Peter Hain said: "We have reached the point where the parties must decide how they want Northern Ireland governed.
"They can have devolved government restored and an end to locally unaccountable direct rule.
"But if this opportunity is not taken then the assembly will cease to meet, MLA salaries and allowances will stop and the May 2007 election will be indefinitely postponed.
"The bill sets an immovable deadline of 24 November, 2006 for getting back to devolution.
"Otherwise, as the prime minister and taoiseach have said, we will have to move on. We are aiming for success.
"We are determined to do all we can to get back to devolved institutions but it is for the parties to make it happen."
Earlier this month, Northern Ireland's politicians were told by the British and Irish governments that the assembly would be recalled on 15 May.
They were also given the 24 November deadline for establishing the executive, with parties being given six weeks to elect an executive.
If that fails, the 108 members get a further 12 weeks to try to form a multi-party devolved government. If that attempt fails, salaries will stop.
The British and Irish governments would then work on partnership arrangements to implement the Good Friday Agreement.
Closing the assembly, if attempts to revive it fail, is expected to cost hundreds of thousands of pounds.
On Wednesday, the BBC learned that if the assembly ceases in November, the government is prepared to hand members up to £1.7m to cover their expenses.
All 108 assembly members will be in line for a winding-up allowance of as much as £16,000 each.
Devolved government at Stormont was suspended in October 2002 following allegations of a republican spy ring.
Three men accused of being implicated in it were later acquitted.