Signs are evident of a possible breakthrough in a dispute involving railway signal workers in Scotland.
Rail staff are angry over a change in their shift patterns
It comes as services got back to normal after a 48-hour strike over shifts.
The BBC has learned that there has been contact between employers, Network Rail, and the RMT union about setting up a meeting between the two sides.
The RMT will meet on Friday afternoon to decide on further possible action, which could include a four day strike and widening action across the UK.
Union leaders had warned earlier that they were considering widening the strike action by balloting staff in England and Wales.
It follows the collapse of talks between Network Rail and the RMT on Monday.
Network Rail said that the possibility of another strike was absolutely staggering.
ScotRail said it could be the evening before services were back to normal.
The Glasgow to Edinburgh service had been reduced to every half hour, while other services across the country were also badly hit.
The row is over proposed changes to shift patterns and centres on how a 35-hour week, agreed last July, is to be implemented nationally. It has been largely accepted in England and Wales.
The RMT executive committee will be meeting in London.
The union's general secretary, Bob Crow, had said earlier on Friday that he would be recommending further industrial action in Scotland and for the balloting of the rest of the signal workers in Britain.
The network is predicted to get back to normal by the end of Friday
Transport Minister Tavish Scott categorically rejected claims that the Scottish Executive had done nothing to avert the strike and said he had urged Network Rail to bring in conciliation service Acas.
Both Network Rail and the RMT told the BBC's Newsnight Scotland programme that the first active intervention by the executive came on Thursday.
But Mr Scott said: "I spoke to the person who is responsible for Network Rail last Thursday - we discussed what might happen this week and I urged him to take every possible step to bringing this matter to fruition, to make sure that the talks between the union and Network Rail as employer were sensible, constructive and came to a conclusion without the need for strike action."
James King of rail group Passenger Focus said the impact of the industrial action on the public and the economy had been significant.
He told BBC Radio's Good Morning Scotland programme: "Over the three days of the strike so far we estimate that had the trains been running normally, something like 600,000 journeys would have been made.
"A significant proportion of those will not have been made - at enormous economic and social cost to those affected."
The Scottish National Party's transport spokesman Fergus Ewing accused the Scottish Executive of not acting quickly enough.
He said: "Our government, who we elected to administer £338m of public money put into the railways, should bring together both sides to have a calm, dispassionate talk about the issues in dispute."
Union chief Mr Crow said: "All we want is the agreement that was reached with Network Rail last summer to be applied in Scotland, just as it has been everywhere else in England and Wales."
He also claimed untrained staff had been taken from south of the border to man signal boxes and added: "If they're going to bring scabs up from England to Scotland it's our intention to ballot everyone in England and Wales for the defence of the rest of the signal workers in Scotland."