TOUGHER rules to stamp out a repeat of government "bias" in the run-up to last year's North-East assembly vote were demanded yesterday by the elections watchdog.

The Electoral Commission called on ministers to observe a "purdah" from the moment a campaign begins, instead of only 28 days before polling.

It follows allegations that the Government mounted a biased information campaign in a failed bid to persuade North-East voters to say Yes to an elected assembly last November.

The Tories were furious when Your Region, Your Choice leaflets featured pictures where people with thumbs up were smiling - while those with their thumbs down were stony-faced.

The leaflets also contained questions and answers such as: 'Will elected regional assemblies reduce bureaucracy? - Yes.'

They were reprinted within 28 days of polling to correct inaccuracies, a decision later backed by the High Court after opponents of the assembly sought a judicial review.

In a report issued yesterday, the commission said: "The Government should not use public money after the referendum period begins.

"If it does, it should adhere to a self-imposed restriction period of at least 28 days prior to the distribution of postal ballots." The recommendation was welcomed by Caroline Spelman, the Tory local government spokeswoman, who said Deputy Prime Minister John Prescott had tried to skew the poll.

"Tougher laws need to be put in place to prevent any repeat of such abuses by ministers during any future referendum," she said.

The commission also called for a review of spending limits and the appointment of a regional counting office, but found that the ballot had been well run.

Its chairman, Sam Younger, said: "The referendum was successfully run, which reflects well on all those involved, particularly the chief counting officer and his staff."