CHAOS on the railways begins in earnest once more today, with travellers between York and Leeds forced to turn to the buses.

But Railtrack insists that the two weeks of delays will be worth it for commuters - who will benefit from faster journeys and improved reliability early in the New Year.

A fleet of more than 100 buses is to run in place of trains on a number of routes into Leeds as the £165 million station improvement scheme moves up a gear - this includes transferring all signalling equipment and 15 staff to York.

Buses laid on by Northern Spirit can carry up to 1,000 passengers an hour in each direction and it is expected that during the day it will be a "turn up and go" service - so when a bus is full it will leave.

"It is a bitter pill for commuters to swallow," said a spokeswoman for Railtrack.

"But the work at the station will mean faster services, it will mean less disruption and more flexibility on the trains.

"Although the work on the station as a whole will not be completed until May 2002 there will be immediate benefits to passengers from York."

She added that £80,000 had been spent on getting the message across to commuters and the decision to close the line was made more than two years ago.

There will be a limited train service from York and Selby to Crossgates for people making local journeys and replacement buses to and from Leeds will be provided to connect with these services.

Customers from Selby are advised to go to York and connect on to Transpennine Express trains to Huddersfield and Manchester.

Transpennine Express trains between the North East and Manchester and Liverpool will be diverted between York and Huddersfield to avoid Leeds, with journey times remaining the same.

Railtrack's 17 days of intensive engineering will involve more than 350 engineers working round the clock to complete track renewal and commission new signalling across the station safely and on time.

Work starts at the east end of the station today, to re-lay track and overhead line. At the west end, work will begin to connect in new tracks to existing rail.

Howard Keal, spokesman for Northern Spirit, said: "It is a huge achievement to keep services going through Leeds station while building work is going on all around.

"Ultimately it would lead to improved punctuality and reliability - and minutes shaved off the journeys.

"There would be the capacity to lay on more trains."

Leeds is the second busiest station outside London, carrying as many as 65,000 passengers a day and more than 900 trains.