Train passengers have been warned they will face “significant disruption” on Sunday after strike action by rail workers disrupted travel on Saturday.

ScotRail is running a skeleton service on August 20 due to industrial action by Rail, Maritime and Transport union (RMT) members of Network Rail, who have walked out in the long-running dispute over pay, jobs and conditions.

The action on Saturday comes after workers walked out on Thursday.

The dispute does not involve ScotRail staff, however the company said it will have a major knock-on effect on the train operator’s ability to provide services as the RMT action involves Network Rail staff in Scotland.

Limited services were running in the Central Belt, Fife and the Borders between 7.30am and 6.30pm on Saturday.

David Simpson, ScotRail service delivery director, said: “It is very unfortunate to see such widespread disruption across the whole of the Great Britain rail network and we know this will be frustrating for ScotRail customers.

“Regrettably, this strike action by RMT members of Network Rail means that we will not be able to operate the vast majority of our services during the period of strike action.”

ScotRail warned that there will be “significant disruption” on Sunday due to the reopening of Network Rail signal boxes at different times throughout the day following the strike action on Saturday.

It said that services will start later than normal due to this.

Members of the RMT, the Transport Salaried Staffs’ Association (TSSA) and Unite walked out for 24 hours on Saturday, affecting Network Rail and a number of train companies across the country.

RMT general secretary Mick Lynch rejected suggestions that rail workers would agree to the current offer on the table if the union put it to a vote.

Asked on BBC Breakfast on Saturday whether he has evidence to the contrary, Mr Lynch said: “Absolutely, I did a meeting on Wednesday evening the night before the strike of 14,000 RMT members in an online rally and our members are out today demonstrating.

“I speak to thousands of our members every week, we consult at least 600 Network Rail reps on a weekly basis, and we know exactly what the mood of our members is.”

The RMT claims Network Rail is attempting to impose compulsory redundancies and cuts to maintenance work and has accused rail chiefs of putting public safety at risk.

Gordon Martin, regional organiser for the RMT in Scotland, said members have turned out in big numbers at picket lines with solidarity expressed by members of other trade unions and “phenomenal support” from the public.

He said: “Meaningful talks are the only way this dispute will be resolved and it’s time the Government allowed Network Rail and the Rail Delivery Group the means required to reach resolution with RMT negotiators and find an outcome which benefits the workforce and the people of Scotland and the rest of Britain.”

Transport Secretary Grant Shapps has urged Mr Lynch to put Network Rail’s pay offer to workers for a vote.

In a letter to Mr Lynch on Saturday afternoon, the Transport Secretary said the railway operator’s proposal of an 8% pay rise over two years is “fair” and members should have the opportunity to resolve the dispute.

Andrew Haines, Network Rail chief executive, said: “It saddens me that we are again having to ask passengers to stay away from the railway due to unnecessary strike action, when we should be helping them enjoy their summers.

“We have made a good and fair offer but, with the exception of our TSSA management grades who accepted the deal, our unions are refusing to let our employees have a say, and sadly that means more disruption on the rail network.”