More than 9,000 postal workers have gone on strike in London and parts of Scotland over jobs.

The Communication Workers Union (CWU) said the industrial action is being held because of a failure by bosses to honour a 2007 modernisation agreement.

A CWU spokeswoman said: "We are getting the cuts (jobs), but we are not getting the modernisation of the postal service."

She said the action had been well supported and caused disruption to deliveries throughout London and in Edinburgh. More industrial action is planned across Scotland on Saturday.

Royal Mail said the three largest offices in London are not affected by the strikes and that some 1,400 management volunteers had been drafted in to help keep the post moving.

It condemned the strike, saying it was at odds with the union's claim to support modernisation.

David Ward, the CWU's deputy general secretary, said it is only a matter of time before staff cuts without pledged fresh investment, in machinery for instance, will have a major impact on the service.

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