Laidlaw made his fortune with an events, conference, and newsletter business which he founded over 30 years ago and sold last summer for Ô£768 million. His stake was a reported Ô£714 million. Even before the sale, the London Sunday Times named him the 101st richest person in Britain, worth an estimated Ô£499 million.

Laidlaw has also been an active contributor to Britain's Conservative Party, and was made a life peer in 2004.

The ENO has been through a rough patch recently; the company lost its chairman, chief executive, and music director over the past three months; it barely avoided a staff strike; and is plagued by severe financial problems. The company recently appointed John Berry artistic director; it is still searching for a new music director and chairman.

Laidlaw's donation, if is confirmed, would be timely, as the furniture group MFI has completed its Ô£300,000 sponsorship of Wagner's Ring cycle. Sky Television will provide Ô£5 million over six years from 2003 to 2009.