The referendum on a "mini-Parliament" for Yorkshire could be postponed, the Government admitted yesterday.

Local Government Minister Nick Raynsford astonished MPs by hinting the Electoral Commission could suggest pressing head with an all-postal ballot in the North East, but not in other regions.

The referendum in regions judged "unsafe" would then be postponed, almost certainly until after the next General Election, pencilled in for June.

In his Commons speech, Mr Raynsford made clear the North East had a long and successful history of all-postal voting, with "very few indications of anxieties".

Significantly, he did not mention successful postal voting in Yorkshire and the Humber or the North West, the third region staging a referendum on November 4.

The Government is under fierce pressure to find a way out of holding ballots in Yorkshire, where polling suggests the "Yes" camp is heading for defeat.

Many Labour MPs believe it is madness to hand the Tories the momentum of defeating devolution with Westminster elections just seven months later.

Until yesterday, ministers had suggested the Commission's looming report into all-postal voting in last month's local elections would decide whether all three polls - or none - would go ahead.

But yesterday Mr Raynsford suggested the Commission might decide an all-postal ballot was unsafe in just one, or two, regions.

He said: "It would then be appropriate to proceed in one region on the basis already proposed while deferring, or adopting a different approach, in another one."

The minister added: "If there are concerns, it's right to address them wherever they might be, rather than adopt a blanket approach."

The Government has made clear privately that it will not go back to traditional polling booths, because of the risk of a disastrously low turnout.

It insists there is no time to switch to individual registration of postal votes - the Commission's long-standing advice. That points to a postponement until well after the June election.

Bernard Jenkin, the Tory local government spokesman, said the decision whether to postpone in a particular region would clearly be in the hands of ministers, not the Commission.

He said the Commission had been asked to assess if there was "evidence leading to a conclusion that it was unsafe" or "suggestions that there is a need for regulatory improvement". Mr Jenkin said: "The Electoral Commission's report is a pretext to call the whole thing off. It leaves the Government a lot of wriggle room."

The Commons last night approved the necessary referendum orders. The House of Lords is expected to approve them early today.

That would leave time for Deputy Prime Minister John Prescott to publish a draft Bill, setting out the proposed powers of the assemblies, before MPs leave Westminster for their summer break tonight.