Walsall North MP David Winnick told the Commons on Thursday that the emergence of the "ambiguity or loophole in the law" might encourage Northern Ireland Protestants and Catholics to attach conditions to donations.

Earlier this week it emerged that a transplant co-ordinator agreed to a white donor's demand that their kidney should not go to a black person.

The case has sparked outrage but doctors have admitted there is little they can do to stop people placing restrictions on who could receive their organs.

Mr Winnick asked Commons Leader Margaret Beckett: "Are you aware that it's totally unacceptable - under any circumstances - for racist conditions to be attached?

"This could lead to religious conditions being put, say, in Northern Ireland - Catholic or Protestant."

Mrs Beckett said: "I think the whole House is appalled by what has been reported and an immediate investigation has been launched into how this came about and to make sure that this never happens again."

Sectarian history

In another development a leading transplant surgeon said on Thursday that he has experienced problems with sectarian organ donation in Northern Ireland.

Director of the transplant unit at Manchester Royal Infirmary, Bob Johnson said that in the past kidneys from Northern Ireland were marked for Protestants or Roman Catholics.

He said: "We have previously had problems when the Troubles in Northern Ireland were at their height.

"We had conditions that kidneys were not to go to Catholics."