President Xi Jinping offered the world a vision of a Chinese-driven "Asia-Pacific dream" on Sunday, as Beijing hosts a regional gathering that underlines its growing global clout.

"We have the responsibility to create and realise an Asia-Pacific dream for the people of the region," the Chinese Communist chief told a gathering of business and political leaders that precedes the annual Asia-Pacific Economic Cooperation (APEC) leaders' gathering.

The 21-member APEC groups 40 percent of the world's population, almost half its trade and more than half its GDP, and the summit will be attended by leaders including US President Barack Obama, his Russian counterpart Vladimir Putin and Japanese Prime Minister Shinzo Abe.

It will see Beijing push its preferred Free Trade Area of the Asia-Pacific (FTAAP), while Washington is driving its own Trans-Pacific Partnership (TPP).

The TPP is seen as the economic element of the much-touted US "rebalance" to Asia and so far brings together 12 APEC nations including Japan and Australia -- but not China.

Obama left Washington Sunday, with the White House saying he was expected to have "candid and in-depth conversations" with Xi, after Secretary of State John Kerry last week described the two powers' relationship as the "most consequential" in the world.

"For the Asia-Pacific and the world at large, China's development will generate huge opportunities and benefits and hold lasting and infinite promise," Xi said.

He later welcomed Russian President Vladimir Putin, with whom he has a shared outlook on issues such as trade, investment and geopolitical interests, including a wariness of the United States.

It was "time to gather fruit" from "the tree of Russian-Chinese relations", Xi told Putin, as the two sides signed agreements stepping up their multi-billion-dollar energy and resources cooperation.

- Chinese dream -

Xi told the business meeting his "Asia-Pacific dream" was based on a "shared destiny" of peace, development and mutual benefit in the region.

The comments have echoes of the "Chinese dream" he regularly speaks of, an unspecified but much-discussed term with connotations of national resurgence.

Beijing -- a veto-wielding permanent member of the UN Security Council -- is leveraging the decades-long boom that has made it the world's second-largest economy to increase its regional and global heft.

But it stresses a policy of non-interference in other countries' internal affairs -- a stance that has enabled it to do business with leaders seen as pariahs in the West.

Its relationship with the United States has been marred by tensions over trade disputes, cyberspying and human rights issues, while Beijing is embroiled in enduring disputes with Tokyo over islands in the East China Sea, and with rival claimants in the South China Sea.

Under Xi, it has been asserting those claims more firmly.

"China wants to live in harmony with all its neighbours," he said Sunday.

Nonetheless, relations with Japan have plunged in recent years with both sides sending ships and aircraft to the islands, which are controlled by Tokyo and claimed by Beijing, raising fears of clashes.

Hopes of an ice-breaking formal meeting between Xi and Abe on the sidelines of the summit have risen following statements by the two countries agreeing to try to improve ties.

But Japanese officials say the key sentence in their statement was "very carefully written" to avoid Tokyo formally acknowledging that there was a dispute on sovereignty over the islands.

"We did not give in to the Chinese demand," one official said.

- 'Not that scary' -

China's decades-long economic boom has seen it overtake Japan as the world's second-largest economy. But its growth reached a five-year low in the third quarter.

Xi said the risks it faced were "not that scary" and slower expansion was expected as its economy matures.

China currently suffers from a deflating property bubble, a crackdown on corruption blamed for curbing some business, and weak demand from Europe.

Even so it was expected to invest more than $1.25 trillion abroad over the next decade, Xi said, while outbound Chinese tourists would exceed 500 million over the next five years.

As "China's overall national strength grows", he told his audience, it would be able and willing to offer "new initiatives and visions for enhancing regional cooperation".

A draft summit communique seen by AFP calls for a "strategic study" on the Beijing-backed FTAAP. But Michael Froman, the US Trade Representative, told reporters Sunday: "It's not the launch of a new organisation, it's not the launch of a new FTA."

FTAAP, he said, was a "long-term aspiration" to be achieved only through other existing negotiations such as TPP, which was "clearly" the priority for the world's biggest economy.

The communique refers to "the eventual realisation" of the FTAAP.

But whether the leaders will endorse the so-called "Beijing Roadmap" towards the FTAAP remained unclear.