The ballots in Yorkshire and the Humber and the North West were put on hold over concerns about electoral fraud and may not take place until next year.

Mr Prescott told delegates at Labour's policy forum: "We promised the people and we must carry out the promises."

A poll in the North East is to go ahead as planned on 4 November.

Opponents have said they believe the postponed polls will not now be held until after a general election - and may not take place at all.

No new polling day has been set for the ballots in Yorkshire and the Humber and the North West. Local government minister Nick Raynsford said they could not take place until next year at the earliest.

Watchdog report

But ministers have insisted they remain committed to regional assemblies in all three areas.

They say there are no concerns on all-postal votes in the North East but they want to wait for a watchdog's report before deciding on the others.

The Electoral Commission is due to report at the end of August on the pilots of all-postal voting in this June's local and European elections.

Conservative shadow minister Bernard Jenkin said last week that the postponement of votes meant they had effectively been cancelled.

Liberal Democrat spokesman Edward Davey, a supporter of regional assemblies, said delaying the polls was a "sad day for democracy".