HUNDREDS of railway signal workers in Scotland are to vote on strike action - threatening chaos for thousands of travellers.

The Rail Maritime & Transport Union today revealed it was to ballot 400 Network Rail workers after accusing the firm of refusing to hold meetings to resolve the dispute.

The union claims NR failed to honour a 35-hour week agreement which settled a national pay and hours dispute involving signal workers last year.

General secretary Bob Crow said there had been a flood of complaints from his members in Scotland that NR was "wilfully misinterpreting" the deal.

He added: "It is bad enough that managers are attempting to change agreed rosters unilaterally, but threatening to discipline members who rightly stick to their booked terms is simply unacceptable."

Mr Crow accused NR of avoiding meeting the union, adding: "That leaves us with no choice but to ballot for action."

The ballot will be completed by mid-February and strikes could start at the end of next month.

A Network Rail spokesman today said: "We sincerely hope that strike action can be avoided."