Passengers have been warned not to travel unless 'absolutely necessary' today as train services are slashed by another walkout by rail workers across several companies in an ongoing row over pay.
Only a handful of services are expected to run on key routes in Scotland for part of the day, with some areas of the country having no services all day.
Unions Aslef and the Rail, Maritime and Transport union (RMT) have voted "resoundingly" to take strike action against the companies they say have failed to give rail workers a pay rise matching inflation.
Network Rail workers who are members of the RMT are staging two 24-hour stoppages on Saturday, October 1 and Saturday, October 8, as part of a dispute over pay.
ScotRail has warned passengers that "significant disruption" will be expected on the network as signallers and safety critical staff walk out as part of the RMT strikes.
The rail operator has urged travellers to check the app and website ahead of travelling.
While the rail operator usually runs about 2,150 services per day, over the next two Saturdays it will only run trains on 11 routes across the central belt, Fife, and the borders.
On October 1 and October 8, ScotRail will run 379 trains - one more than it was able to put on during strike action in August.
While ScotRail drivers are not striking, drivers across other companies such as LNER and the TransPennine Express will walk out on Saturday.
Services will resume on Sunday, but these may face disruption as signal boxes are restarted.
Postal workers from the Communication Workers Union will also take strike action on Saturday in an ongoing dispute over changes in working terms and conditions.
Rail and postal workers will gather at Edinburgh Waverley on Saturday morning to show their "mutual solidarity" for each other and demand a fair wage from their employers.
Aslef Regional Organiser Kevin Lindsay said: "Workers have had enough of bosses paying themselves huge dividends and salaries whilst expecting workers to take real terms wage cuts.
"We are delighted to be standing shoulder to shoulder with our brothers and sisters in the RMT and CWU who are also facing the same fight and struggle as our members.
"We will also stand together and show our solidarity with other workers in struggle."
David Simpson, ScotRail service delivery director, said the knock-on effects of the industrial action would impact on services on both Sunday October 2 and Sunday October 9 as well.
Andrew Haines, Network Rail chief executive, said: "Despite our best efforts to compromise and find a breakthrough in talks, rail unions remain intent on continuing and co-ordinating their strike action.
"This serves only to ensure our staff forgo even more of their pay unnecessarily, as well as causing even more disruption for our passengers and further damaging the railway's recovery from the pandemic.
"Passengers who want to travel this Saturday, and indeed next Wednesday and next Saturday, are asked only to do so if absolutely necessary. Those who must travel should expect disruption and make sure they check when their last train will depart."
Further industrial action will take place later in the month, when RMT members working for ScotRail will walk out on strike on Monday October 10.
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