Hartford Group, the owner of London restaurants Montana and Pharmacy, may sell off four of its sites in a bid to recover from a tough year of trading.
The company warned in July that its profits for the year to31 December would be "significantly lower than expected".
It blamed the fall partly on poor weather over the summer (Caterer, 6 July, page 5).
Hartford is now reviewing its options and is understood to be seeking buyers for the 150-seat Idaho restaurant in Highgate, and the 80-seat Utah in Wimbledon.
Two development sites in Ascot, Berkshire, and Loughton, Essex, are also up for grabs, as is the Congress, Hartford's private dining club, which closed in April.
Hartford chief executive Kevin Finch said the London restaurant market had "gone soft" and that the company was reviewing its strategy.
It is understood that Idaho and Utah remain profitable and will be sold only if the group can get a very good price for them.
Further options for Hartford include merging with another company and opening new restaurants outside London in order to spread overhead costs.