Mr Brown said the UK was "not proposing" to go to the IMF
Gordon Brown has rejected speculation the UK might have to seek a bailout from the International Monetary Fund.
The G20 summit in London agreed to increase resources available to help troubled economies to $500bn (£340bn).
Treasury minister Stephen Timms and Business Secretary Lord Mandelson said this would remove some of the "stigma" of using the facility.
Asked whether the UK would go to the IMF, the prime minister said he was "not proposing to do so".
The Conservatives seized on the ministers' remarks about "stigma".
'Not first in queue'
During a Commons debate on the G20, shadow chancellor George Osborne asked: "What exactly did the financial secretary [to the Treasury - Mr Timms] have in mind when he said it?"
The Tories have warned that spiralling state debt could force the government to follow in the footsteps of Labour former chancellor Denis Healey, who approached the IMF for a bailout as the economy struggled in the 1970s.
Questioned on Channel 4 News over whether the UK might access this funding again, Lord Mandelson replied: "I don't think we are going to be first in the queue."
He added: "I don't think we are going to be in the queue."
At the G20's closing press conference, Mr Brown said: "Countries have offered that they will take up the IMF facility - I think Mexico has yesterday - but we are not proposing to do so."
Mr Timms was quoted as telling a meeting earlier at the G20 that Mexico's move showed "we have gone beyond the era of stigma."
The remarks echo those he gave in a Commons debate on 17 March, when he said that "there needs to be reform of the instruments through which the IMF can lend.
"In those ways, we want to overcome the problem of stigma that has been attached to IMF programmes in the past, to the extent that some countries feel it is politically impossible to contemplate approaching the fund."