Britain’s most luxurious bus service will come to an end next month after sustaining heavy losses.

The MegabusGold “sleepercoach” runs overnight between Scotland and London, with leather seats for day use which convert into fully-flat beds.

It was launched in 2013, with overnight services year-round from Aberdeen, Dundee, Edinburgh, Glasgow, Inverness and Perth to Victoria Coach Station in London.

Two drivers staff each bus. Journey times are similar to Caledonian Sleeper overnight rail services, at 8 hours, 30 minutes from Edinburgh to London. The coach stops only for crew changes; there is an on-board toilet.

But with intense competition from airlines as well as rail operators between Scotland and London, Megabus suffered heavy losses on the routes.

Each bus, custom-built in Belgium, cost £500,000. The company was unable to command the average level of fares, thought to be around £50 per passenger, required to break even on the service.

The decision by Ryanair in 2014 to launch flights from Edinburgh and Glasgow to Stansted reduced average fares on Anglo-Scottish links.

On the very last day of operation, 21 May 2017, a one-way berth from Edinburgh to London currently costs £29.50 on Megabus. The lowest overnight rail fare on the Caledonian Sleeper is more than three times as much, at £90. But Ryanair is selling seats that evening from the Scottish capital to Stansted airport for £19.

Unlike Megabus, the budget airline charges extra for luggage and does not offer passengers lie-flat beds and an amenity kit. Yet even when the travelling time and fares to and from the airports are taken into account, the Ryanair option tempted away too many potential passengers. When The Independent tested the service, the fellow passengers were mainly foreign visitors keen to save on overnight accommodation between the UK’s two biggest tourist cities.

The company has quietly announced the service is to close. A statement on the website says: “The services - which launched in 2013 - represented an innovative and new travel product and have helped provide a value-for-money long-distance transport option over the past four years.

“While the services have proved popular with a loyal core base of customers, unfortunately the overall level of demand has been below the level required for us to be able to continue the routes.