Deputy Prime Minister John Prescott is spending his sixth day in hospital, being treated for pneumonia.
John Prescott will stand down as deputy leader on 27 June
He missed Thursday's Cabinet meeting, which he was due to chair while Tony Blair is at the G8 summit - Commons leader Jack Straw took his place.
Mr Prescott's spokesman said there was no marked change in his condition - he is in a high dependency unit.
On Wednesday the 69-year-old's son said he was sitting up in bed and joking with hospital staff.
David Prescott said his father wanted his thanks passed on for the messages of support sent from across the world, as well as to staff at the hospital, whom he thanked for their "fantastic treatment".
The deputy prime minister was moved to a high dependency unit on Tuesday so he could be monitored more closely because of his age, and the fact he suffers from diabetes.
Mr Prescott is stepping down as Labour deputy leader and deputy prime minister on 27 June - the same time as Mr Blair.
He was taken ill on Saturday on a train from Hull to London.
During his 10 years as Mr Blair's deputy, Mr Prescott has been generally in good health.
However, in 2002 it was announced he had suffered from type two diabetes for a number of years, managing the condition with medication.
And he was taken to hospital on Christmas Day 2006, when he was treated for kidney stones.
Pneumonia is an inflammation of the lungs, usually caused by an infection.
Many different bacteria, viruses and even fungi can bring on the illness - although Mr Prescott's official spokesman said he did not know what had caused the pneumonia in his case.
Symptoms include difficulty in breathing, chest pain, coughing and fever. It is frequently resolved within weeks.