Services between Edinburgh and Bathgate are unable to run due to the fault, and delays are expected on the Edinburgh to Falkirk line.
This is due to a potential signal fault at Newbridge Junction that initially affected lines between Haymarket and Falkirk and Bathgate and Edinburgh.
Network Rail engineers are on site and attempting to fix the problem.
A statement from Network Rail confirmed: “Trains are now able to run between Edinburgh and Dunblane, Edinburgh and Alloa, Edinburgh and Queen Street, but trains between Bathgate and Edinburgh are still unable to run.”
ScotRail have put ticket acceptance on the Edinburgh Trams to help people reach Edinburgh Gateway, Edinburgh Park, Haymarket and Waverley.
The travel company also reminded people that replacement buses are in operation on Saturday between Glasgow Queen Street and Stirling because of engineering works.
