Labour’s John McDonnell has claimed victims of the Grenfell Tower fire were “murdered” by “political decisions”.
Speaking at Glastonbury Festival on Sunday, the shadow chancellor blamed the decision to “view housing as only for financial speculation”.
At least 79 people are feared to have died in the fire in west London, which began in the early hours of 14 June.
Housing minister Alok Sharma said it was “disappointing” that people wanted to make it “a party political issue”.
It is thought the building’s recently-installed cladding may have helped the fire to spread.
Cladding is being tested from as many as 600 tower blocks across England.
So far, cladding on 60 high-rise buildings in 25 areas has failed, and none has passed.
The prime minister ordered a public inquiry on 15 June and she is due to chair a meeting of the Grenfell Tower Recovery Taskforce on Monday.
Mr McDonnell, the MP for Hayes and Harlington, was speaking in a panel debate at Glastonbury’s Left Field event, chaired by Guardian journalist John Harris.
He said: “Is democracy working? It didn’t work if you were a family living on the 20th floor of Grenfell Tower.
“Those families, those individuals – 79 so far and there will be more – were murdered by political decisions that were taken over recent decades.
“The decision not to build homes and to view housing as only for financial speculation rather than for meeting a basic human need made by politicians over decades murdered those families.
“The decision to close fire stations and to cut 10,000 fire fighters and then to freeze their pay for over a decade contributed to those deaths inevitably, and they were political decisions.”
A source close to Mr McDonnell confirmed the quotes were accurate.
Mr Sharma, who replaced Gavin Barwell as the housing minister following the general election, said the cladding in question had been installed over a wide time period and under councils controlled by different political parties.
Pressed on a timescale to complete the testing, he said the