Some commuter train services in Sussex will not be back to

normal until the summer following delays in repairing cracking tracks, the rail regulator says.

Railtrack has been given a new back-to-normal deadline for most services of May 21 by the rail regulator, Tom Winsor.

Mr Winsor said fewer than a quarter of the 28 train companies would achieve the original target of Easter because of delays in finishing the major repair programme launched after the Hatfield crash last October.

There could be continued delays on the Brighton to Rugby line, which stops at Gatwick, East Croydon and Clapham Junction, until June 30.

Passengers on the route are currently facing delays of about 20 minutes because of speed restrictions imposed north of Watford until the track is repaired.

Railtrack said it was aiming to complete work on the line by April 17 and insisted services on the Brighton to Rugby route should be operating normally by May 21, when the summer timetable comes into force.

Elsewhere in Sussex, most services are running to a normal timetable although there are still speed restrictions at Norwood Junction, on the Brighton to London line, while repair work is carried out.

Gatwick Express is among the companies promising to be running normally immediately after Easter.

The rail regulator issued an enforcement notice but has not imposed fines if Railtrack fails to meet the May 21 deadline.

However, train companies such as Connex could lodge further compensation claims for millions of pounds if Railtrack does not get the network running normally by that date.