THE new Caledonian Sleeper service has arrived in London more than three hours late following signalling problems on the line.

The new carriages in the £150 million fleet of trains made their debut yesterday night on the Lowlander route between London and Glasgow/Edinburgh.

But the train from Glasgow/Edinburgh to London arrived at 10.27am this morning instead of the scheduled arrival time of 7.07am after signalling issues.

Ryan Flaherty, Serco's managing director for Caledonian Sleeper, said: "We apologise to guests affected by delays to our services last night.

"These were as a result of signalling problems across the network.

"We are engaging with Network Rail to understand why these issues occurred."

READ MORE: New carriages for Caledonian Sleeper trains subject to further delays

Network Rail said there was also an issue with the train itself.

A Network Rail spokesman said: "A signalling fault near Carstairs caused significant delays to trains on Sunday, including the sleeper services.

"Our engineers were on site quickly to find and repair the fault, however, the complex nature of the issue meant it was several hours before full repairs were completed.

"We apologise to all those passengers who had their journeys disrupted."

The National: The club car in the new fleetThe club car in the new fleet

The trains are set to be introduced between London and Aberdeen, Inverness and Fort William shortly.

The fleet has been part funded by capital grants from Scottish ministers and the UK Government.

Scottish Secretary David Mundell: "It is fantastic to see the launch of the new Caledonian Sleeper service.

"The UK Government has invested £50m in the new fleet, improving vital connectivity between Scotland and England, and improving the service for the thousands of passengers. I was pleased to travel on their debut journey and look forward to using this service for years to come."

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