President Barack Obama flew on Friday to his native Hawaii to host Asia-Pacific leaders, buoyed by Japan's decision to enter talks on a deal that could rewrite the rules of US-Asia trade.

Launching a nine-day Pacific tour, Obama was due to touch down at 0830 GMT on Saturday in his birth city of Honolulu, where police had erected fences on laid-back Waikiki Beach and sniffer dogs scoped the palm tree-lined harbor.

Obama will host the Asia-Pacific Economic Cooperation (APEC) forum at the start of a trip that seeks to leave the economic gloom of America and Europe behind and look towards a region that is vital to future US prosperity.

"We obviously believe that the world’s strategic and economic center of gravity will be the Asia-Pacific for the 21st century," Secretary of State Hillary Clinton said after talks with senior APEC officials.

White House aide Ben Rhodes said that Obama will deliver the message that 'the United States will continue to play the role it has throughout the last half century in being an anchor of security and stability in the region'.

US plans to reorient on Asia after a punishing decade pursuing wars in Iraq and Afghanistan, received a fillip on the eve of the APEC summit when Japanese Prime Minister Yoshihiko Noda joined trade negotiations.

The Trans-Pacific Partnership (TPP), signed in 2005 as an obscure arrangement between just four members -- Brunei, Chile, New Zealand and Singapore -- has suddenly become the cornerstone of a US free trade drive.

The entrance of Japan, the world's third largest economy, into the talks was seen as imperative if the TPP is to be transformed into a meaningful pact that will knock down trade barriers across the Pacific.

"The Trans-Pacific Partnership ministers expect that the leaders of the TPP countries will be able to announce the broad outlines of a high-standard, ambitious, 21st-century trade pact," US Trade Representative Ron Kirk said.

"Of course, many of us believe that TPP can be the basis for a long-term APEC goal: a Free Trade Area of the Asia-Pacific," he told reporters after meeting trade and finance ministers ahead of Sunday's leaders' summit.

Experts warned that the entry into the negotiations of Japan, which has strong protections for its crucial farming industry, would complicate a process that could now drag on for years.

"To join the negotiations, Japan must be prepared to meet the TPP's high standards for liberalizing trade and to address specific issues of concern to the United States regarding barriers to agriculture, services and manufacturing trade, including non-tariff measures," Kirk said.

The elephant in the room is China, the world's second largest economy, which risks being left out in the cold if the trade zone takes off.

It has criticised the US ambitions as beyond the reach of developing economies in the fast-growing region.

The decision to join the talks was a thorny one for Noda as Japan's exporters are keen to expand their markets but farmers fear that a massive flow of cheap food imports would destroy an already weak agricultural sector.

With Japan's entry, 10 nations are now in talks for an expanded TPP. The others are Australia, Brunei, Chile, Malaysia, New Zealand, Peru, Singapore, the United States and Vietnam.

The vision is for an initial group of economies to form the core of the grouping. Membership will remain open, with more economies added progressively after they agree to the same commitments as existing members.

Several other APEC countries, including Canada and Indonesia, have said they may join the pact.

Even China said it was considering it, although the United States is insisting on tough conditions that may preclude Beijing's entry.

The implications for a trans-Pacific FTA are enormous, especially with the Doha Round of global trade talks still in limbo. The 10 countries already involved in negotiations account for more than one-third of global output.

Mexican President Felipe Calderon canceled plans to attend the APEC summit, which concludes on Sunday, after his interior minister died in a helicopter crash near Mexico City.

After leaving Hawaii, Obama will celebrate 60 years of security ties with Australia and make the first visit by a US president to the East Asia summit, set for Bali next week.