On the eve of the fourth national rail strike this summer by members of the RMT, the same union has called a stoppage on the London Underground for Friday 19 August.

The dispute with Transport for London (TfL)is over pensions and jobs.

The timing means three days of disruption for commuters in the London area, because the RMT has two more walk-outs planned for Thursday 18 and Saturday 20 August.

The union says the industrial action has been prompted by “TfL’s refusal to share the details of a draft government proposal they received regarding funding of the transport system in the capital, in secret and without any discussion with their recognised trade unions”.

Previous strikes have closed almost all Tube services in the capital, with knock-on effects the following day.

The union is seeking assurances within a week of no reduction in jobs, no detrimental changes to pensions and no changes to working conditions.

The RMT general secretary, Mick Lynch, said: “Our members will once again take to picket lines in this important dispute over pensions, jobs and conditions.

“They have been messed around by TfL and mayor Sadiq Khan. And to add insult to injury they have not seen the detail of this funding letter from government.

“Unless there can be assurances made about jobs, pensions and detrimental changes to working conditions, then our strike on August 19 will go ahead.”

The Independent has asked TfL for a response.

National rail strikes, such as the one scheduled for Wednesday 27 July, have a significant impact on some parts of the Tube network as well as the east-west Elizabeth line.

In addition, commuters who travel in by rail to one of the London terminus stations and then continue by Underground face problems on each of 18, 19 and 20 August.

London Underground and national rail ridership continues to be significantly below pre-Covid levels – with weekend travel coming back most strongly.

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