A national postal strike is to begin within hours, crippling mail deliveries across Britain.

It comes after the Royal Mail and union bosses failed to reach an agreement in their dispute over pay conditions and modernization.

Up to 120,000 members of the Communication Workers Union (CWU) will stage two 24-hour walkouts on Thursday and Friday.

More strikes are planned in the future, the union said.

Leaders of the CWU met today to consider the outcome of marathon talks between the two sides, which ended in the early hours of this morning.

The CWU claimed the Government and Royal Mail were working together to prevent progress in the dispute.

The CWU said "external forces" were trying to "undermine" the talks, singling out Royal Mail bosses Mark Higson and Adam Crozier and Business Secretary Lord Mandelson.

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