TORIES hit out after the date was announced for a referendum on whether to have an elected assembly for the Yorkshire and Humber region.
The date for the all-postal ballot will be November 4.
Polls will also be held on assembly plans for the north- east and north-west.
Government ministers described it as an "historic opportunity".
But shadow minister for the regions Bernard Jenkin said: "This isn't so much the great north vote as the great north hoax."
He hit out at Deputy Prime Minister John Prescott over the referendums.
Mr Jenkin asked: "How can Mr Prescott justify spending millions of taxpayers' money on an information campaign which doesn't actually give out the crucial information people need to judge his proposals?"
He slammed the regional assemblies as little more than toothless talking shops, without any real powers.
They would take power even further away from local people, he claimed.
A campaign group said council tax bills would have to rise to fund the £25m annual running costs of a Yorkshire assembly.
John Watson, chairman of Yorkshire Says No, said: "The last thing Yorkshire needs is a meddling talking shop costing millions to set up and run which is only going to increase tax and bureaucracy.
"The reality is that the Yorkshire assembly would have no power over public services and control over less than 2% of Government expenditure."
Campaigners for the elected regional assembly claimed the south was prospering while large parts of the north were being left behind.
Jane Thomas, campaign director of Yes4Yorkshire said: "This is not about creating another tier of government – there is already an unwieldy and undemocratic tier of administration at regional level. This is about getting some powers out of Whitehall and Westminster and letting people in the region make regional decisions."
Nick Raynsford, Minister for Local and Regional Government, said: "People in the three northern regions now know that in November they should have a historic opportunity to change the way their region is governed."