By Richard Hartley-parkinson PUBLISHED: 03:57 EST, 17 April 2012 | UPDATED: 04:31 EST, 18 April 2012 Millions of commuters face fresh misery next week as London Underground workers plan a 72-hour walkout. The strikes, which come a week ahead of the mayoral election, stretch over four days and will involve the people who maintain and upgrade the tracks who are unhappy with negotiations over pensions and benefits. The Rail, Maritime and Transport union, which represents around 1,000 staff on the Tube Lines contracts, said its members will walk out at 4pm on Tuesday until the same time on Friday.
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Workers to walk out at 4pm on Tuesday until 4pm on Friday next week
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Strikes will affect Piccadilly, Jubilee and Northern Lines
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TfL says strike action is 'completely unnecessary'
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Chamber of Commerce says strike will cost 'millions'
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Boris Johnson spokesman said it was 'no surprise' that Ken Livingstone's friend was calling for strikes ahead of the London mayoral elections
'The @placeholder should call off this needless strike and work to find a settlement before any damage is done.'