Tung had agreed to do the interview during his recent visit to the US, and the has learned that his aides in Hong Kong did not know of it in advance. That means it was not arranged before he left, which is not quite like the prudent Tung.

During the interview, two important messages concerning the leadership change emerged from Tung, an authoritative person, who is himself a "state leader". One, that without doubt Xi will be the next Chinese leader; and, two, President Hu Jintao may stay on as military head "for some time, based on past practice".

Since Tung stepped down as Hong Kong's chief executive in 2005, he has been very low-key, never touching on any sensitive issues in public. He rarely comments on Sino-US relations, playing his role as China's top "lobbyist" to the US because of his and his family's close connections with American political and business leaders.

But now, Tung seems to be the de facto spokesman for Beijing on top state issues. This clearly shows the trust he has won from Zhongnanhai and its future master, Xi.

The Tung-Xi relationship can be traced back to the late 1990s, when Xi was governor of Fujian , the province closest to Taiwan. People close to Tung told the that Xi, who was eager to promote the development of the province, constantly sought advice from Tung on how to attract investments from Taiwan and Hong Kong.

Tung encouraged the powerful "Fujian clan" in Hong Kong, a group of influential businessmen with origins in Fujian, to contribute to their home province. He also encouraged other Hong Kong businessmen to look beyond Guangdong and to put their bets on the strategically important Fujian. Meanwhile Tung is said to have given many tips to Xi on how to deal with overseas investors.

Friendship steadily grew between Xi and Tung, son of a world-famous shipping tycoon. To Xi, Tung was a kind, experienced teacher in terms of business and world affairs.

No wonder that when an under-fire Tung suddenly resigned as chief executive in 2005, Xi, then the party boss of Zhejiang , was the first senior mainland official to extend a warm welcome. He invited Tung and his wife to pay a private visit to the province and tour Tung's hometown of Ningbo , which is in Zhejiang, "to relax and rest". To Tung, experiencing the greatest setback of his career, Xi was a friend in need.

During the chief executive election campaign earlier this year, Tung was believed to be canvassing support from Xi and other leaders for Leung Chun-ying. Leung won the top job but now faces tough challenges.

Tung earlier openly voiced his continued support for Leung amid rumours that Leung might not be able to hang on. Now Tung has assured the world that Xi will be the next leader in Beijing, and given Tung's deep relationship with Xi, will that help Leung in any way?

There is no clear answer. While Tung was chief executive, he had a close relationship with the then-president, Jiang Zemin . Hong Kong's second chief executive, Donald Tsang Yam-kuen, did not have that kind of personal contact with a top Chinese leader and neither does Leung. But Tung may provide Leung with a convenient channel to Beijing.

Nevertheless, Beijing's assessment of Hong Kong, and the performance of Leung and his team, will rely more on how well Leung delivers. In the end, personal relationships can never be counted on too much.