Buffett kicked off the Giving Pledge project with Bill and Melinda Gates in June in an effort to get all current and former members of the Forbes 400 list to pledge half their wealth to philanthropy.
And if there were any bitter memories of Mr Huhne's alleged (broken) pledge not to stand against the former Lib Dem leader in 2006, he was now anxious to stress their mutual closeness.
Former Secretary of State Hillary Rodham Clinton secured a pledge from Iraq to inspect the flights last year, but the official said that since then only two aircraft have been checked by Iraqi authorities.