The long-awaited opening of the Islamic centre on the banks of the River Cherwell in Oxford is years away.

More than £50m has been spent on the building so far, with contributions coming from a wide range of countries including Kuwait, Turkey, Malaysia and Saudi Arabia.

But £25m is still needed to complete the scheme. Work on the Oxford Centre for Islamic Studies started on the 325-acre site off Marston Road in 2002 and the complex was originally scheduled to open in 2004.

The centre said it was now hoping the governments of the UK, Spain and Russia could be persuaded to help make up the shortfall.

In addition to the costly materials being used, such as marble and French limestone, money is needed to build up an endowment fund.

OCIS registrar David Browning said: “It still requires a lot of money and costs are going up all the time.

“But there will be no short cuts. This is something worth doing and worth doing properly.

We are determined that it will be a first class academic institution.”

An elaborate Islamic garden is also to be created, named in honour of Prince Charles, who has taken a close interest in the project.

The centre’s determination to seek funding from a wide range of governments, to ensure it was viewed as an international institution and not linked to any branch of the Islamic faith, has added to the complexity of the fundraising.

The policy has resulted in Government's funding particular projects, with the centre to have a Kuwait library, a 220-seat Malaysia auditorium and an Istanbul forecourt.

Dr Browning said dealing with so many different governments had proved a complicated process, but he rejected suggestions that some had reneged on early promises to help.

He said: “When a pledge has been made it has always been honoured, but we would very much like to see the UK government involved.

“Our hope is that it may be ready in maybe a couple of years.”

The centre was established as an associated institution of Oxford University to encourage scholarly study of Islam and the Islamic world.