The Royal Mail could take between three and four weeks to clear a backlog of letters left by wildcat strikes which appeared to be coming to an end yesterday.
As more than 20,000 wildcat strikers began returning to work yesterday, the Post Office started the hefty task dealing with a backlog of tens of millions of letters, by re-opening sealed letter boxes and urging the public to "carry on posting".
An agreement to end the unofficial industrial action, concluded in the early hours of yesterday morning, included a guarantee by management not to victimise the employees who took the unlawful action unless they were guilty of threatening behaviour.
The settlement was reached after Allan Leighton, the chairman of Royal Mail, and Billy Hayes, the general secretary of the Communication Workers Union (CWU), intervened in negotiations.
The accord commits both sides to achieving a national deal to introduce single-letter delivery by 10 December a key efficiency issue for management. Union negotiators have also agreed that all local arrangements must comply with national agreements by the end of the year.
However, there were fears last night that the deal remained "fragile" and that local activists still needed to be convinced. Fresh talks today at the conciliation service Acas will have to address concerns among employees about working practices and it is by no means certain that the nationally agreed document will be respected locally.
Last night strikers had returned to work in much of London, Coventry, Warrington, Hatfield and Chelmsford, and there were signs that most would be back at work by today.
The dispute has cost the Royal Mail tens of millions of pounds and undermined its strategy for returning to profit after suffering heavy losses in the past few years.
Customers in London and other parts of the country were asked to be patient as employees dealt with the mountain of mail that had built up since the walkouts began a fortnight ago.
The disputes started in the wake of an official 24-hour strike over London allowances when management allegedly attempted to impose new working methods on staff returning to work. The industrial action spread to Oxford, Warrington, Coventry, Essex and Buckinghamshire when employees refused to deal with letters diverted from strike-hit offices.
Malcolm Bruce, Liberal Democrat trade and industry spokesman, said the "understanding" reached gave hope that the unofficial strike would tail off. However, he warned: "It is very frightening that the postal service can be at the mercy of this kind of wildcat action."
Tim Yeo, the shadow Trade and Industry Secretary, said: "Ministers should be quicker to protect customers and should make it clear now that any future strike, official or unofficial, would lead to the immediate suspension of Royal Mail's monopoly on mail delivery."
An official spokesman for the Prime Minister said No 10 welcomed news that an understanding had been reached.
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