Election officials have warned ministers that a postal strike could skew the election results in marginal seats if a poll is held next month.

Returning officers told The Times that they are seeking urgent talks with the Ministry of Justice and the Royal Mail to discuss the impact of any extended postal strike, which would hit postal votes and the electoral register.

Returning officers fear that the two 48-hour strikes planned for this weekend and early next week might be extended if Gordon Brown calls an election soon.

David Monks, spokesman for the Society of Local Authority Chief Executives, said yesterday that after legal consultation it had been decided that if there was a strike there would be no change to the election officers’ existing policy of not counting postal votes that arrive after 10pm on polling day.

He added: “The unions are bound to threaten industrial action near the end of October to cause maximum damage. I am very concerned that we will be forced to reject votes that arrive late, which could affect results in marginal constitituencies.”

Postal vote application forms were being sent out or delivered by hand by all three parties this week in an attempt to boost turnout.

Anyone can apply to their local council for a postal vote up to 11 days before polling day. But the form then has to be returned, a ballot paper sent out and then the ballot paper returned, all within ten days.

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