Which trains will run in Scotland during the strike?

ScotRail will have to again cancel the vast majority of trains during the latest strike action by the RMT union this weekend.

The strike by about 40,000 Network Rail staff is part of a dispute over pay, working conditions and redundancies that will badly affect services across Scotland, England and Wales as well as the London Underground.

When is the strike?

The latest 24-hour RMT strike is being held on Saturday, and follows one on Thursday.

Passengers have been warned that disruption will not be confined to the day of the strike, with services also being impacted on Friday night and Sunday morning.

Which services will still be running?

ScotRail will run a very limited service on 11 routes in the central belt, Fife, and the Scottish Borders, with no trains anywhere else on the strike day.

Trains will only run from 07:30 on the routes that will remain open, with the last trains departing well before 18:30.

The routes are:

• Edinburgh Waverley - Glasgow Queen Street via Falkirk High: two trains per hour 

• Edinburgh Waverley - Helensburgh Central: two trains per hour 

• Glasgow Central - Hamilton/Larkhall: two trains per hour 

• Glasgow Central - Lanark: two trains per hour 

• Edinburgh Waverley - Glasgow Central via Shotts: one train per hour

• Edinburgh Waverley - Inverkeithing: two trains per hour

• Edinburgh Waverley - Tweedbank: two trains per hour

• Edinburgh Waverley - North Berwick: one train per hour

• Glasgow Queen Street - Larbert: one train per hour

• Glasgow Queen Street - Falkirk Grahamston: one train per hour

• Milngavie - Springburn: two trains per hour

You can check this page for further information.

Trains in England and Wales will also be badly affected, including services between London and Scotland on both the East and West Coast mainlines.

Passengers have been urged to only travel if it is necessary, and anyone who does so should plan ahead and expect disruption.

There will not be any replacement buses or taxis throughout the period of industrial action.

Anyone who has bought a ticket they are unable to use will be able to claim a full refund.

Why can't ScotRail run more trains?

Network Rail staff operate signal boxes and maintain other key railway infrastructure

This dispute does not involve ScotRail staff, but it relies on Network Rail workers to operate signal boxes and maintain the track across the country.

Signal boxes are crucial to the rail network because they control train movements and allow the railway to operate safely.

Network Rail has said the strike means it will only be able to open signal boxes on a few routes, so it would not be safe for trains to run anywhere else.

It will also take time for signal boxes across the country to reopen the day after each strike, which is likely to cause further disruption.

Large signalling centres in central Scotland are expected to be able to operate from 07:15, but it could be later in the day before manual signal boxes elsewhere in the country open again.

Here are updated lists of trains that will be running on Friday 19 August and Sunday 21 August.

Why is the strike happening?

The RMT is in dispute with the UK government and rail companies including Network Rail about pay, job cuts and changes to terms and conditions.

They say salaries should increase to reflect the rising cost of living.

Network Rail says its latest offer is worth more than 5%, but this depends on workers accepting "modernising reforms".

However, the RMT argues that this is a "paltry sum" and represents a real terms pay cut.

The RMT says another issue is plans by Network Rail to cut 2,500 maintenance jobs, as the company tries to save £2bn over the next two years. The union insists those jobs are "safety critical".

Network Rail says there would be no more than 2,000 job losses - and that all redundancies can be voluntary. It says it would not consider any changes that would make the railways less safe, but stresses modernisation is needed.

The industrial action is also being supported by members of the Transport Salaried Staffs' Association and Unite who work for Network Rail and some other rail companies.

It is not related to a separate dispute between the RMT and ScotRail which saw the union threatening strike action after its members - including ticket examiners, conductors and station staff - rejected a 5% pay rise earlier this month.