A rail strike which caused chaos for thousands of commuters across Scotland today could be extended across the UK if the dispute is not resolved, union bosses have warned.

Passengers suffered a second day of travel misery as the 48-hour stoppage by signal workers continued.

Thousands of Scots struggled to get home from work yesterday following the start of the walkout at noon.

The strike, which is over a dispute about working hours, went ahead after the collapse of talks between Network Rail and the Rail, Maritime and Transport union (RMT).

Union officials claim employers have failed to honour a 35-hour week agreement made last year and have also accused Network Rail of abusing roster agreements.

RMT general secretary Bob Crow warned today that signal workers in England and Wales could be balloted on strike action if the dispute in Scotland is not resolved.

Commenting on the prospect of further UK-wide action, he told BBC Radio Scotland: "Unless management sit down and resolve this very, very quickly, then the executive committee will consider balloting the entire signal workers in England and Wales as well."

Network Rail bosses said they have been prepared to negotiate since the talks between both sides broke down on Monday this week.

Hundreds of services have been cancelled or forced to run on a reduced timetable during the stand-off by around 400 signal workers in Scotland, which is due to end at noon tomorrow.

The north of Scotland has been particularly badly hit by the action, with no trains running north of Stirling.

Services cancelled include Inverness to Wick, Thurso to Kyle of Lochalsh, Aberdeen to Inverness, Aberdeen to Glasgow and Edinburgh, Inverness to Glasgow and Edinburgh, and Perth to Glasgow.
Stagecoach said it filled most of the 1,200 extra coach seats it provided on its Scottish Citylink and megabus for those affected by the strike.

More than 20 additional coaches were put on stand-by in Aberdeen, Dundee, Edinburgh, Glasgow, Inverness and Perth.

In the central belt, Network Rail and First ScotRail said they hoped to run between 20% and 30% of a normal service during the strike.
Trains on one of the country's busiest routes between Glasgow and Edinburgh started up at 7am today, with a half-hourly service instead of every 15 minutes.

Many travellers were forced to take the bus or car instead.
Train operator First ScotRail said: "We deeply regret the inconvenience to our customers.

"We are providing as many services as possible in difficult circumstances."

David Simpson, route director for Network Rail Scotland, labelled the action "regrettable" and "unnecessary" and insisted the company was willing to engage in discussions with the RMT.

"We've offered to go to (arbitration service) Acas to have this matter resolved, but RMT have refused that and passengers are suffering as a result," Mr Simpson said.

Scottish Transport Minister Tavish Scott called on the RMT to use Acas.

He told BBC Radio Scotland: "The employers have offered at any time to take that forward and the union have up until now said they won't.

"I am asking the union today to get in that process."