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 to 31 December would be "significantly lower than expected". It blamed the fall partly on poor weather over the summer.
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, its 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 only be sold if the group can get a very good price for them.
Further options for Hartford, which is listed on the AIM stock market, include merging with another company or opening new restaurants outside London in order to spread its overhead costs.