Tube strike: Union walkouts 'could escalate' in London Published duration 29 November 2010

image caption Commuters faced long queues for buses when Tube services were hit on Monday morning

The fourth 24-hour strike over job cuts in London Underground ticket offices has ended, with unions warning their walkouts could escalate in 2011.

Industrial action lasting two or three days was possible in the new year, the Rail, Maritime and Transport (RMT) union and the Transport Salaried Staffs' Association (TSSA) said.

But there would be no strikes over the Christmas period, they added.

All lines were disrupted during the latest strike, which ended at 1830 GMT.

Services were not expected to return to normal until Tuesday morning, however, because of the knock-on effects of the walkout.

About 50 Tube stations were closed on Monday evening and the following lines were still affected:

Bakerloo - suspended between Queens Park and Harrow and Wealdstone

- suspended between Queens Park and Harrow and Wealdstone Central - suspended between White City and Liverpool Street and between Hainault and Woodford via Chigwell

- suspended between White City and Liverpool Street and between Hainault and Woodford via Chigwell Circle - suspended

- suspended District - suspended between Earls Court and Kensington Olympia/Edgware Road, and between Turnham Green and Richmond

- suspended between Earls Court and Kensington Olympia/Edgware Road, and between Turnham Green and Richmond Hammersmith & City - suspended between Liverpool Street and Barking

Jubilee - suspended between Wembley Park and Stanmore

- suspended between Wembley Park and Stanmore Metropolitan - a special service is in operation

- a special service is in operation Northern - a special service is in operation

- a special service is in operation Piccadilly - suspended between Arnos Grove and Acton Town, and Acton Town and Uxbridge

- suspended between Arnos Grove and Acton Town, and Acton Town and Uxbridge Victoria - a special service is in operation

- a special service is in operation Waterloo and City - a special service is in operation

The dispute centres on the future of 800 ticket office staff at Tube stations.

London Underground said their roles were no longer required as the widespread use of Oyster cards had reduced demand for paper tickets, but there would be no compulsory redundancies.

The RMT said removing the employees would jeopardise passengers' safety and increase the risk of muggings and other offences.

"We are moving towards an escalation of the action in the New Year," said Bob Crow, the general secretary of the RMT.

"I will not be recommending any action this side of 2 January, but come 2011 we will have to consider escalating strikes to more than one day."

He said the union's executive would consider its next move later this week.

But London Underground's managing director, Mike Brown, said that "after consulting with the union leaderships on this for more than six months, trying to establish what specific safety concerns they may have, we offered a further six weeks to discuss our plans".

"For them to reject this and threaten more strike action next year is staggering, and will be seen by Londoners for what it is - an attempt to hold our city to ransom," he said.