RAIL passengers in York could face further delays before being able to catch a new non-stop service to London.

Grand Central was due to start running trains to the capital on May 20, but it has emerged that their engines will not be ready in time.

They must now lease some stock from elsewhere for the short term, or delay the launch date by six weeks.

Grand Central's managing director, Ian Yeowart, said: "Our own diesels will not be ready. The passenger vehicles will almost certainly be ready, but to ensure available power, we have been talking to other people.

"Hopefully we can come to some sort of arrangement, but until then we cannot make any announcement."

He added: "If we do get delayed, it will be by weeks not months.

"We are running, at the moment, about six weeks behind."

The service was originally due to launch last December, but the company was unable to lease the trains it had hoped to.

Meanwhile, Grand Central has announced it is to order three ultra-fast Chinese trains to enhance its service - the first time China has sold trains to Europe since opening its economy to the west.

The 140mph Polaris trains will be able to take advantage of any relaxation in the East Coast Main Line speed limit, and will replace the 125mph High-Speed Trains (HSTs).

Mr Yeowart said: "The delivery of the rebuilt HSTs is of course the first target, but the discussions that have taken place over many months on the new-build trains gives us confidence that they will be an exceptional replacement for the HST - and of course will meet all the regulatory and safety requirements for trains introduced to the UK rail network."

Giles Fearnley, chairman of Grand Central, added: "We are delighted that this exciting project can continue to move forward."

He said he was confident Network Rail would see the benefit of the investment. Stock will be made available by Grand Central's sister company Sovereign Trains, and the Polaris train sets will be delivered to the UK for final testing in 2010.

David Shipley, director of engineering of Sovereign Trains, said: "A great deal of effort and resource has been made in preparing Grand Central for operation, and we are sure passengers will be impressed not only by the new trains but also by the re-built HSTs when they come into operation.

"The Polaris units will be very much focused on passenger requirements and expectations and we look forward to working with colleagues at Network Rail to ensure the trains meet their expectations on reliability, weight and operational capability."

Grand Central will operate three daily services to and from London later this year, and is seeking to run a fourth.