Australian Prime Minister Kevin Rudd told David Cameron to enjoy the feeling of becoming Britain's new leader and offered his congratulations in a phone call on Wednesday.Rudd said Cameron, 43, and his pregnant wife Samantha should take time to savour reaching office, at the head of a coalition government, before the hard work begins. "Just within the last hour I spoke with David Cameron and I certainly congratulated him on being elected to the high office," Rudd told Fairfax Radio Network."I also suggested he and his wife just take a moment of quiet time to enjoy it all because in about an hour's time it all starts."Rudd also praised outgoing prime minister Gordon Brown as a "very good man", hailing his contribution in steadying the free-falling world economy at last year's G20 summit in London. "Gordon Brown is a very good man. His contribution particularly at the London summit last year, which he chaired, was fundamental in breaking the fall in the global economy which was occurring at the time," he told Sky News.Cameron, Britain's youngest prime minister in about two centuries, leads a Conservative-Liberal government -- the country's first coalition administration since World War II -- after inconclusive polls last week.