Thousands of Essex commuters could face chaos after a rail union announced a ban on overtime work.

Trains could be delayed or even cancelled after the Rail Maritime and Transport union announced its members at Balfour Beatty would stop working overtime from tomorrow in a dispute over terms and conditions of employment with the contract firm.

Balfour Beatty is contracted to carry out work on rail lines between London and Southend by Railtrack, including cleaning leaves off the tracks.

However, train operators working from Southend hope the overtime ban would not affect their services.

A spokesman for c2c, which runs trains from Southend to Fenchurch Street, said: "It is hard to gauge what affect the ban will have on our services.

"If Balfour Beatty has enough staff not to need anyone to carry out overtime, the effect should be minimal.

"We have heard nothing from Railtrack to warn us of any problems but we will be monitoring the situation."

A spokeswoman for First Great Eastern, which runs trains from Southend to Liverpool Street, London, said it had not been informed by Railtrack of any problems.

The action coincides with the start of the "leaf fall season" when trains are delayed by leaves rotting on the tracks.

Bob Crow, the union's assistant general secretary, said: "We have been negotiating with the company for some time but they have still not come up with an acceptable package."

A spokeswoman for Railtrack confirmed Balfour Beatty carried out contract work for the company and provided it with equipment for c2c and First Great Eastern lines.

However, she said: "We are not expecting the action will have a noticeable affect on services. We have other suppliers of equipment we can rely on if Balfour Beatty cannot get the equipment to our lines."

A spokeswoman for contractors Balfour Beatty said: "We can confirm the union is planning to carry out an overtime ban.

"The company is continuing to take part in talks. It is disappointed at the impending action but we are reviewing the possible impact it could have and we are working to see how we can meet the obligation of our contract with Railtrack."

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