Japanese Prime Minister Shinzo Abe kicked off his first overseas visit since his election victory in December in a bid, analysts said, to bolster Japan's regional influence and try to contain China.

Before embarking on Wednesday on the trip, to three Southeast Asian nations, Abe said the strategic environment of the Asia-Pacific region is undergoing a "major change".

Abe and his Vietnamese counterpart Nguyen Tan Dung held talks in Hanoi. Abe will also visit Thailand and Indonesia. Japanese media have carried quotes from government sources saying that the main purpose of the visit is to strengthen maritime cooperation with other countries against China.

Japan's Prime Minister Shinzo Abe (center) arrives at Noi Bai airport in Hanoi, Vietnam, on Wednesday. Abe is in Hanoi for a two-day visit to Vietnam, the first leg of his Asian tour. [Photo: Agencies]

Abe expressed concern at what he described as China's increasing maritime presence. Japan is considering helping Vietnam's infrastructure program and may also provide more loans, Japan's NHK Television reported.

Jia Duqiang, a researcher at the Chinese Academy of Social Sciences, said China should be confident of its position and reach out to its neighbors to counter Abe's diplomatic blitz. Abe turned his focus quickly to the region after Washington told him earlier this month that a visit to the US would be difficult to schedule at such short notice.

"Abe's trip is political posturing and will have few, if any, benefits. Hanoi will surely consider ties with Beijing when dealing with Tokyo, and Hanoi will not miss the big picture simply because of the South China Sea issue,'' Jia said.

Ties between China and Japan ran into severe turbulence in September after Tokyo illegally "purchased" part of the Diaoyu Islands, which have belonged to China for centuries.

Japan's exports to China, and China-based outsourcing businesses, have been hit and reports said some Japanese entrepreneurs are avoiding investing in China and are turning to emerging economies in Southeast Asia.

"ASEAN members have a comparative advantage," said Liu Jiangyong, a specialist on Japanese studies and the deputy dean of the Institute of Modern International Relations at Tsinghua University.

Tokyo is eager to restore its influence in the region, said Yang Bojiang, a Japanese studies specialist at the Chinese Academy of Social Sciences.

"Southeast Asia is like a backyard for Japan, and the region also hosts key shipping routes.''

The visit to Hanoi is not a coincidence, Liu said.

Choosing Vietnam for a Japanese leader's first trip abroad is a strategic decision to rein in China, Liu added.

Prominent figures from both ruling and opposition parties have come to China in a bid to ease the tension.

China's top political adviser Jia Qinglin held talks on Wednesday with visiting former Japanese prime minister Yukio Hatoyama.

Jia said Beijing looks forward to developing ties and both countries should handle differences through dialogue, Jia said.

Hatoyama agreed and said both countries should boost cooperation.

On Monday, Kenji Kosaka, a lawmaker from Japan's ruling Liberal Democratic Party met with Vice-Foreign Minister Fu Ying in Beijing.

Kyodo said Japan's New Komeito party leader Natsuo Yamaguchi will visit China on Tuesday.

New Komeito are in coalition with the LDP.

But Abe has allowed members of his Cabinet to go on a series of visits to Southeast Asian countries and Australia in January.

"The Japanese government is trying to solidify its relations with other countries in the region and strengthen its bargaining power before talking to China,'' Narushige Michishita, an associate professor at the National Graduate Institute in Japan, told Reuters.