The Duke of Westminster's property group Grosvenor today added its voice to the growing list of firms to declare the boom of recent years is over.

Chief executive Jeremy Newsum, in his final year as head of the £13 billion company which owns vast swathes of Mayfair and Belgravia as well as estates in Cheshire, Lancashire, Scotland and Canada, said he expects values in London and beyond to fall this year.

It came as Grosvenor reported a 3% rise in profits for 2007 to a record £524 million as its international business helped offset the slowdown in Britain. Returns from rent and capital gains fell from 15.5% in 2006 to 14.4% last year. "Industry returns are unlikely to recover in 2008," said Newsum. "Like everyone else, we are detecting changes in the market, which isn't a bad thing because markets cannot go up for ever.

"We expect values to fall. Whether the fall is confined to 10%, or there is a larger fall of 25%, we think that is a relatively good thing over time as London needs to be able to compete. At the moment it is expensive."

Grosvenor wrote off a further £48.8 million at its £1 billion Liverpool One development. It lost £140 million on the project last year.