The year before, Baird spent New Year's in New York, staying in Canadian Consul General John Prato's residence.
Baird's office said Thursday morning that both diplomats are friends with the minister.
Campbell and Baird have been friends since before Baird's appointment as a cabinet minister in 2006. In Prato's case, the friendship was said to date back 20 years, to before his days in federal politics.
Both diplomats currently report to Baird as minister and live in government residences as part of their official roles.
The minister's office, however, said that both Campbell and Prato do pay some rent for their personal living quarters as part of their arrangements as Canada's representatives abroad.
Baird stayed in Campbell's residence from Dec. 26 to Jan. 2, 2013, after Campbell invited him as "a personal friend to his apartment" while the high commissioner was out of town.
"No staff were present as it was the holidays," wrote ministerial spokesman Joseph Lavoie in a message to CBC News. "There was no one working there, so no expenses incurred."
Consul general away
"The minister personally paid for the trip himself, including [the] flight, and personally paid for transportation to and from airport by cab, as well as around London."
The New York stay ran from Dec. 28, 2011, to Jan. 2, 2012, when the consul general was also not using his government accommodations.
"The minister has two friends who happen to be heads of missions. He has taken them both up on their offer to stay as a personal guest of theirs," Lavoie wrote. "On both occasions, no expenses were incurred and no taxpayer monies were used."
In February, the Harper government announced that Campbell's residence in London, the John A. Macdonald building in Grosvenor Square, will be put on the market as part of a consolidation of the Canadian government's real estate in London. Macdonald House, which includes both office and residential space, was last valued at $800 million.
Senate Government Leader Marjory LeBreton pointed to the pending sale as a way to save money, and defended Baird's visit.
"This trip did not cost taxpayers a single dime. Minister Baird has saved taxpayer dollars in recent years by staying at official residences rather than in expensive hotels when travelling on official business," she said during the Senate's question period.
Liberal Senator Jane Cordy responded that Baird's trip had nothing to do with official business. Cordy said one of the friends who stayed with Baird at the residence was David Forestell, the chief of staff to Natural Resources Minister Joe Oliver.
"Those are pretty good accommodations for an eight-day stay in London. Eight days of accommodations, free of charge, in a mansion that is owned by the taxpayers of Canada and that is valued at more than $500 million. Who can sign up to stay there?" Cordy said.
Baird is currently travelling on government business in the Middle East. He has no vacations planned at this time, according to his office.
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