The Northern Ireland secretary has said he will take steps to allow a budget bill to be introduced in Westminster.
James Brokenshire said talks between the Democratic Unionist Party (DUP) and Sinn Féin had failed to reach agreement to establish an executive.
Sinn Féin said the latest talks had “ended in failure” but added the party was prepared to resume negotiations.
The parties are attempting to end a 10-month deadlock that has left the region without a devolved administration.
Sinn Féin’s Stormont leader Michelle O’Neill said her party had tried to be “flexible”, but “endless talks without conclusion are not sustainable”.
Mr Brokenshire said he would be ready to withdraw the budget bill if an an executive is formed before December.
The budget would only deal with 2017-18 financial year, he said, adding that it did not mean a return to direct rule from Westminster.
Northern Ireland’s two largest parties have failed to reach an agreement in spite of numerous rounds of discussions since March, after the Northern Ireland Executive collapsed amid a bitter split between the parties in January.
It is understood they have made little progress on key dividing issues.
Sinn Féin’s demand for legislation to give official status to the Irish language viewed as the stumbling block in the negotiations.
The DUP has said it wants to see the government press ahead with its budget plan, but Sinn Féin has warned that doing so would force an end to the talks.
Mr Brokenshire said there were “consequences” of not having an executive in place to put forward the legislation this week.
“It is now very unlikely that an executive will be in place within a timetable to pass a budget by the end of November, which is the point at which we and the Northern Ireland Civil Service assess that Northern Ireland will begin to run out of resources”, he said.
“No government could simply stand by and allow that to happen.”
Sinn Féin said the confidence and supply arrangement between the DUP and the Conservative party had “compounded” the problems the parties faced.
The prime minister made the £1bn deal with the DUP after losing her majority in June’s general election.
‘Latest possible juncture’
Speaking at Stormont on Wednesday, the Northern Ireland secretary said he would be seeking independent advice on what steps should be taken to “reflect the current circumstances in MLA pay”.
Mr Brokenshire had previously said he would examine the issue of assembly members’ salaries in the absence of devolution, amid calls for their salaries to be docked.
The secretary of state stressed “important progress” had been made in discussions between the DUP and Sinn Féin.
He also said the British and Irish governments would continue to work with the parties as they proceed with ongoing talks.
Irish Foreign Affairs Minister Simon Coveney said Mr Brokenshire had taken the budget decision with the “utmost reluctance and at the latest possible juncture”.
Both the UK and Irish government had “spared no effort” in supporting the talks between the DUP and Sinn Féin, he added.
“The issues under discussion – particularly those on language and culture – go to the heart of the divisions in society here in Northern Ireland,” he said.
“However, I have always believed that it is possible to reach an honourable compromise.
“There have been sincere efforts to stretch for that and measurable progress in finding an agreed outcome had been made, but we are not there yet.”
SDLP leader Colum Eastwood insisted the Secretary of State’s move was direct rule. He pointed to the DUP-Tory deal as an issue at the talks.
“A Tory-DUP government will do nothing for the rights of people in the north,” he said. “It only strengthens the DUP’s intransigence.”
“It will do nothing for the rights of Irish language speakers, the LGBT community or [Troubles]victims,” he added.
Northern Ireland business leaders have also expressed disappointment.
“Our members deserve better than a ‘care and maintenance’ administration with important decisions on business rates, infrastructure and many other areas, not currently being taken by Ministers, said the chief executives of Hospitality Ulster and Retail NI, Glyn Roberts and Colin Neill.
“Political instability is bad for business and our economy as a whole.”