Before Joe Biden left China this week, the last thing Vice President Xi Jinping told him over dinner was simple: he wants to be friends.

If that happens, the U.S. vice president may be the first Western leader to have an inside view into the nature of the little-known man who is expected to take over the helm of the world's second largest economy in 2013.

Biden spent about five days in China on a multi-nation Asia tour designed to shore up relationships with key allies and assure the world that, despite its deficit woes, the United States is not in decline.

But his journey had another strategic mission: get to know his counterpart, 58-year-old Xi, who is expected to replace President Hu Jintao in roughly 18 months.

Biden came away with impressions that could have an important bearing on perhaps the most important bilateral relationship in the world.

During the visit, U.S. officials said Xi appeared keen to get more comfortable with the United States despite the many disputes that divide them. His projected warmth runs counter to some analysts' predictions that Xi could turn to angry nationalism to prop up his authority.

I found him to be totally engaging, Biden said of Xi in an interview with three reporters traveling with him in Asia.

In my one-on-one meeting with him, as well as very small group meetings...he genuinely is open about the nature and the extent of their problems, what they're going to have to deal with, short-term and long-term.

Biden described Xi as both pragmatic and strong, even praising him in a meeting with Hu in Beijing.

Xi, who studied chemical engineering and is married to a popular folk singer, seemed as interested in getting a window into U.S. thinking as Washington was in understanding his.

Tall and slightly stooped, Xi grew up in the privileged yet demanding confines of a Communist leader's family. He saw the tumult and suffering of China's grassroots firsthand during the Cultural Revolution (1966-76), when, like many urban youths, he was sent down to work in the poor countryside.

In public, Xi appears confident and comes across as straight-forward. He does not smile as much as his cheerful U.S. counterpart but is less stiff than the more reserved man he is to replace, Hu.

GETTING TO KNOW YOU

In 2009, Xi made a famously blunt warning that he does not want China to shoulder the responsibilities of a full-fledged superpower while it focuses on amassing wealth and power.

Some foreigners with full bellies and nothing better to do engage in finger-pointing at us, he said during a visit to Mexico. First, China does not export revolution; second, it does not export famine and poverty; and third, it does not mess around with you. So what else is there to say?

But on a policy level, Biden said Xi understood the symbiotic relationship between the U.S. and Chinese economies and wanted to avoid big surprises between the two nations.

This interdependency -- I got a sense that he fully appreciated, Biden said.

The part that I think there has to be continued discussion on is the strategic relationship because, you know, I don't think there's anything that's (in) either of our interests that would put us in conflict except a misconception, misperception, misunderstanding of any action either one of us took.

With disagreements ranging from Taiwan and Tibet to human rights, foreign exchange policy and free trade, there is plenty of potential for rifts in relations to widen rapidly, particularly as Beijing's economy and influence grows.

U.S. President Barack Obama wants to avoid misunderstandings by building personal relationships, and Biden's visit to China was a down payment on that process.

The two vice presidents met several times during Biden's stay in China, which U.S. officials viewed as a strong signal that Xi was serious about forging a personal connection.

Biden said he and Xi had good chemistry. In Chengdu at a final private dinner, the Chinese leader said he wanted to have more than a formal relationship.

The last thing that he said in my one-on-one...(was) he wanted to build a personal friendship, Biden told reporters.

There's just a practical benefit from having a personal relationship with another world leader in times of misunderstanding, in times of differences so that you have a sense of confidence of what you're being told or not told...is more likely to be accurate than not.

Though they have policy and personal differences -- Biden is older and comes from a modest background, Xi is a princeling whose father was a revolutionary comrade of Mao Zedong -- the two men discovered they faced some similar challenges in the world of politics.

U.S. officials said Biden described for Xi the dynamics of dealing with lawmakers in Congress and Xi saw similarities with his own experience as a provincial governor, albeit under a very different system.

SOMETHING IN COMMON

Xi served a long stint as a party official in poor rural areas of Hebei, the northern province that surrounds Beijing.

Subsequently he spent his career largely in provinces known for economic openness, trade and wealth. That, and his late father Xi Zhongxun's legacy as an ally of liberal 1980s party chief Hu Yaobang, has boosted the image of Xi as a potential reformer.

(Xi) talked to the vice president at length about how he would go into all of the villages in his province at least once a year to understand what his constituents were thinking and looking for and wanting, a U.S. official said.

On one level you'd think that these guys have nothing in common, and yet, I think what they found is that as politicians and political leaders, there actually are a lot of commonalities, he said.

Xi is expected to settle into power after early 2013, when a meeting of the national parliament is likely to seal his succession to the presidency.

A U.S. political transition may be taking place at that time, too. Obama and Biden are up for re-election in November 2012.

Before that, however, Xi is expected to make a reciprocal visit to see Biden in the United States.

Kenneth Lieberthal, a foreign policy expert at the Washington-based Brookings Institution, said it appeared the two men were starting to understand each other.

They spent a lot of time together, not all of it in highly scripted discussion, he said.

In terms of the personal relationship, both of these gentlemen are politicians. Politicians are people who become pretty good at reading other folks.

Even with the extent of their talks, for the U.S. vice president, there is still a lot more to learn about Xi.

This is a guy who I think is very solid, Biden said. Now that doesn't mean anything beyond that. He's just solid and he understands that this relationship is worth deepening.