A rail company is planning to take legal action against a train drivers' union whose members are threatening to withdraw rail services on Millennium Eve and New Year's Day.

Connex has had to cancel scores of services into London from southern England over the past two days because its drivers have stopped working overtime in a dispute over hours.

The drivers are refusing to work overtime and rest days and their union, Aslef, says if the row is not settled, they will not work over the millennium.

That action could disrupt the plans of thousands of revellers hoping to travel over the millennium.

Connex, which has two companies - South Eastern and South Central - had offered drivers £1,000 to volunteer to work over the millennium.

But in talks, the union has been seeking a four-hour cut in the working week to 35 hours and an improvement in pensions.

'Protecting customers'

Now Connex says it will take Aslef to the High Court in London on Thursday.

A spokesman said: "Our legal advisers will be issuing proceedings in the High Court to prevent the union's illegal action from impacting further on our customers."

Aslef said talks would be held between the two sides, also on Thursday, to try to resolve the dispute.

The union also wrote to Connex's lawyers saying: "Aslef do not accept that they have authorised any form of industrial action against either Connex company in respect of rest day working or overtime."

The union said drivers had not been instructed to take part in anything that could be considered as unofficial industrial action.

Nearly 30 Connex trains were cancelled on Tuesday morning because of the dispute.