'Post credit-crunch rents are down 20 percent but a long-term tenant could be willing to pay up to 10,000 pounds a week,' the Daily Mail quoted him as saying Wednesday.

A source close to Mittal was quoted saying: 'Mr Mittal has put a lot into the property and doesnot want a cheap sale. Heaes in no hurry.'

Also Wednesday, ArcelorMittal, the world's largest steelmaker, reported its third consecutive quarterly loss.

The Luxembourg-based company said it posted a Q2 net loss of $792 million.

But Mittal, 58, told the Financial Times that emerging economies were coming out of the downturn 'reasonably quickly' and that stimulus spending in the US and Europe was having an impact.

FT Alphaville, the paperaes daily news and commentary service, described the statement as 'an unusually optimistic forecast'.