The RMT has warned that it will stage a ‘week of action’ on the London Underground from 23 to 28 July.

Different grades and sections of the staff will strike during those six days, but details of the planned stoppages have not been released.

The walkouts are part of the continuing dispute between the RMT and Transport for London over jobs, pensions and working conditions.

The union said 600 jobs are at risk, and that ‘London Underground staff stand to be poorer in retirement if TfL's proposed changes go through’.

It has also claimed that more stations may be unstaffed and that safety standards are set to be lowered.

RMT general secretary Mick Lynch said: ‘This week of action will shut down the London Underground and show just how important the work of our members is. Plans by TfL to cut 600 jobs and attack our members pensions are simply unacceptable.

‘We are aware that Mayor of London Sadiq Khan has had the TfL budget cut. However, he needs to align himself with our union and his London Underground staff in pushing back against the Tory government, exposing their damaging agenda to a key part of London transport infrastructure.’

TfL chief operating officer Glynn Barton said: ‘There are no current proposals to change pension arrangements and, although we are discussing with union colleagues a range of proposals to improve how London Underground operates, no employee will lose their job or be asked to work additional hours.’