Council services will be merged
Exeter and Norwich have won their bids to take over all council services in a shake-up of local authorities.
The new "super councils" in Exeter and Norwich will take over all county council roles in the two cities such as schools, roads and social services.
The government is asking Suffolk councils and MPs to reach a consensus on what unitary solution they would like in their county.
Ipswich Borough Council had hoped to be given unitary status.
Ministers have ruled out unitary authorities for the whole of Norfolk and Devon, as they could not succeed without commanding the support of the local councils.
It means local government in the rest of Norfolk and Devon will stay as it is.
The government said the change would benefit local people, with leaders "who know their areas best".
Local Government Minister Rosie Winterton said: "Exeter and Norwich are at the centre of regional economic activity in their areas and their economic performance is crucial for their residents and the wider area.
"That's why today we're putting Norwich and Exeter's local leaders who know their areas best in charge of delivering all local services and at the heart of delivering growth."
Devon County Council, which currently has its headquarters in Exeter, will be left as a mainly rural authority.
Devon already has two other unitary councils, in Torbay and Plymouth.
The Conservatives have said they will overturn the decision if they win the general election.
Elections in 2011
East Devon MP Hugo Swire said: "Exeter is a fundamental part of Devon without which neither can function effectively."
Cornwall's district councils and county council were merged in April to create the unitary Cornwall Council.
The proposals for unitary authorities for Norwich and Exeter will now be voted on by parliament before they become law.
If parliament approves the proposals, the councils can start putting in place transitional arrangements ready for elections to the new councils in 2011.
Leader of Norwich City Council Steve Morphew welcomed the decision: "We always believed a unitary Norwich would be the best solution for local people."
David White, chief executive of Norfolk County Council, criticised the decision.
"A unitary Norwich would be too small to progress big strategic projects, and a weak voice in the region and nationally," he said.
"So this decision simply threatens to put an artificial barrier into the growth of the Norwich sub-region - just when we should be pulling together to get out of the recession and drive Norfolk forward."