New trains have been launched on the East Coast Main Line, five months later than planned.

LNER unveiled the first of 65 new Azuma trains at King's Cross, with the service due to begin on Wednesday.

The first Azuma trains are to run on the main line service between London and Leeds.

David Horne, managing director of LNER, said it would offer "about 10,000 extra fares a week at the lower end of the price range" in the coming weeks.

Plans to introduce the electric-diesel trains in December were abandoned after they were found to interfere with trackside signalling equipment.

The trains, which are modelled on the Japanese bullet train, are being assembled at Hitachi's plant in Newton Aycliffe, County Durham.

Azuma means "east" in Japanese, said LNER.

Mr Horne said: "The new trains are really the start of the transformation on the East Coast route.

"They're replacing trains which are 30 and 40 years old."

He added one of the key benefits of the trains would be the extra capacity.

Karen Boswell, of Hitachi Rail, said: "Putting trains into service is really complex. The balance of building new technology and working with the infrastructure is always very challenging."

Rail minister Andrew Jones said: "There will be more services, the experience on the trains will be better and each train will have many, many more seats.

LNER will increase its fleet from 45 to 65 trains by 2020 with the introduction of the Azuma and journey times will be cut, said publicly owned LNER.

The first stations to be served by the trains are Leeds, Wakefield, Doncaster, Peterborough and London.

After the London to Leeds route, they will be phased in across the rest of the LNER network.