The Executive has agreed a compromise deal
The Stormont Executive has agreed a plan to cut Northern Ireland's local authorities from 26 to 11 by 2011.
The DUP and Sinn Fein said the compromise plan, passed by seven votes to two, would build a firm foundation for strong local government.
It creates four nationalist-dominated councils in the west and south, and six predominantly unionist councils in the north, east and centre.
The UUP was the only party in the Executive to oppose the plan.
North Belfast UUP MLA Fred Cobain said he feared it would mean a mainly nationalist Belfast council.
"Belfast has been sacrificed by a DUP minister," he said.
"What the Provos couldn't do in 40 years, she has done with a stroke of a pen to turn this city green - it's an anti-Belfast agenda."
Environment Minister Arlene Foster - whose department was responsible for the plan - said that the notion that Belfast would be governed exclusively by nationalists and republicans in the future "is a fantasy created by the Ulster Unionist Party".
Sinn Fein assembly member John O'Dowd said Mr Cobain's comments "clearly exposed the sectarian and undemocratic underbelly of a party that fails to recognise that it has no supreme right to rule".
The current 26-council system dates back to the 1970s but, after a review, former secretary of state Peter Hain opted to cut these to just seven.
Sinn Fein supported that plan but the other major parties said they would be too big to preserve local identity and backed a 15-council model.
A Sinn Fein/DUP compromise of 11 new councils has now been agreed. Elections are expected to be held in 2011.
It is understood the SDLP minister Margaret Ritchie, who is in the US, had written to Mrs Foster indicating she was happy with the plan.
Since the restoration of devolution, the shake-up in local government has been the responsibility of the environment minister, who said it was "a very good day, not just for local government, but for this executive as well".
Mrs Foster added: "In order for local government to fulfil its role as leader and shaper of communities, a range of functions will be transferred to the new local councils.
"These include aspects of planning, as well as rural development, the public-realm aspects of local roads functions, urban regeneration and community development, a range of housing-related functions, and local economic development and tourism."
A spokesman for the Northern Ireland Local Government Association, which has been campaigning for greater powers for councils, said they preferred the 15-council model but were happy with 11.
"Whilst we welcome the transfer of planning, regeneration and some further housing functions, we remain disappointed with the limited nature of the overall package," said Arnold Hatch.
"However, we are committed to working in partnership with the executive in the long term to find new ways to maximise the benefits to our citizens."
There has been no indication yet of how many jobs could be lost among local authority workers.