COUNCIL tax bills will soar by £25 a year if the Yorkshire and the Humber region gets an elected regional assembly, it was claimed today.
A new group called Yorkshire Says No vows it would fight Government proposals.
Business figures have already signed up and an appeal was made today for other people to join.
Organisers said the plan would cost people dear - and the assembly would have no real powers.
Deputy Prime Minister John Prescott has announced a public referendum in autumn of next year on the proposals.
The new anti-assembly campaign is likely to be based in Barnsley.
Its chairman will be John Watson, a former president of Bradford Chamber of Commerce.
He said: "I want to encourage people to vote No.
"The Government's own estimate is that it could add £25 a year to average council tax bills."
Mr Watson said it was tempting to believe that what was on offer was a sort of Yorkshire Parliament, as in Scotland.
"But that is not the case at all," he said.
"No real power would be devolved from Westminster.
"The new assembly would be responsible for just 2% of public expenditure in this region - certainly not enough to justify a whole new apparatus of politicians and bureaucracy.
"Everyone in Yorkshire and North Lincolnshire should be very worried about what is proposed."