Civil servants working for the Chancellor ran up a £56m bill on hotels and meals last year, official figures have revealed.
Tory MP Grant Shapps obtained the costs of the Treasury and its agencies for 2005-06, and said Gordon Brown had "a lot of explaining to do".
Shapps, who tabled questions in Parliament to obtain the figures, said that spending appeared to have gone up by £7.7m over the past four years.
"The public will find it unbelievable that a Chancellor who once prided himself on prudence has become the nation's biggest spender, splashing out £56m for him and his staff to wine and dine while staying in hotels in Britain and around the world," he said.
But the Treasury dismissed the accusations, saying the subsistence costs were for 11 different agencies, including £50m from HM Customs & Revenue.
John Healy, financial secretary at the Treasury, said the claim was "ridiculous", as the costs covered 108,000 employees nationwide.
By Daniel Thomas
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