Radical Muslim cleric Abu Hamza and other inmates at Belmarsh prison have refused to eat their lunch in a protest at the jail's high security wing.
The Home Office said 22 men had taken part in the protest
The Home Office said 22 of the 25 prisoners in the unit had taken part in the action, but all intend to eat normally on Wednesday.
A spokesman said they had refused food on the grounds of its quality.
Abu Hamza's lawyer claimed the men were not being properly fed and were having to pay for food to sustain themselves.
Muddassar Arani, who described the incident as a "hunger strike", said the other protesters included the men awaiting trial over the attempted bombings of London's transport network on 21 July.
But the Home Office rejected her claims that the protest began after bread was "thrown across a dirty table" at an inmate.
A spokesman said the men refused to eat on the grounds that the food was "not up to the usual standard".
Tuesday is the day when all inmates at the south London prison receive food they have bought with their own money, he added.
Abu Hamza was sentenced to seven years imprisonment at the Old Bailey in February for inciting murder and racial hatred.