US Secretary of State Hillary Clinton's expected visit this week to the Cook Islands in the South Pacific has raised geo-political concerns over competition among major powers in the region.

Clinton's presence as the most senior US official to attend the Pacific Islands Forum indicates the United States plans to re-engage with the South Pacific, analysts said.

"Attending the forum is part of the US pivot to the Asia-Pacific region," said Da Wei, an expert on US studies at the China Institutes of Contemporary International Relations.

It's also a show of US "soft power" and the Obama administration's increased attention to multilateral organizations, Da said.

Clinton will also pay a two-day visit to China on Sept 4 and 5, during which the two sides will exchange views on Sino-US relations and other issues of common concerns, the Foreign Ministry said on Tuesday.

The two countries' engagement on the Diaoyu Islands, South China Sea and Clinton's recent visits to Asia, Africa and the South Pacific — which have been viewed as encircling China — will likely be high on the agenda, analysts said.

The US State Department is yet to formally confirm Clinton's visit to the Cook Islands, but local media described her visit as the biggest since Queen Elizabeth II came to the country in 1974.

The challenges of climate change and protecting one of the world's last pristine ocean environments are set to dominate the agenda of the Pacific Islands Forum, but on the sidelines of the summit officials are abuzz about Clinton's visit, according to AFP.

The 16-nation forum is largely made up of small island states, along with resource-rich Papua New Guinea and regional powers Australia and New Zealand.

Fiji's suspension from the forum and whether to allow the former member back into the group are expected to be discussed. Fiji was suspended in 2009 after the 2006 military coup, according to Xinhua.

Media reports quoted diplomatic sources as saying that the United States expects the forum to readmit Fiji, and has urged Australia and New Zealand to end their isolation of the country, suggesting they are giving too much room for Chinese moves in the region, according to Xinhua.

Da said the China factor in US re-engagement in the South Pacific should not be played up.

"Although China has increased interactions with countries in this region in recent years, it is still not a major player in the South Pacific," Da said.

Da said it's normal for the US to feel challenged as China rises as a "newcomer" in the South Pacific, an area that has historically had close ties with Washington.

China has sent participants to the forum since 1990, and State Councilor Dai Bingguo is said to attend this year's forum, according to media reports.

Competition is unavoidable as China's influence grows in places where the US once played a dominant role, Da said.

"But such competition should not be overstated. It's not necessary to have a zero-sum game," Da said.

China's presence in the South Pacific is now "a fact of life", said Australian Foreign Minister Bob Carr.

"My message really is that Australia and New Zealand have got to live with the fact that China will want to deliver aid in this part of the world (and) there is nothing we can do to stop it," Carr told the Australian Financial Review.

The US has its own Pacific territories in Guam, the Northern Marianas and Hawaii, but in recent years — with the exception of American Samoa — it has paid scant attention to the South Pacific.

Michael Powles, a senior fellow at the Centre for Strategic Studies in Wellington and a former New Zealand diplomat, said the presence of Washington's top diplomat at the summit would send a pointed message to Beijing that the US intends to re-engage in the region.

"The US has suddenly started doing a lot more in the Pacific after quite a long time of doing the absolute minimal amount, whereas over the last few years China has been pretty active," he told AFP.

Contact the writer at chengguangjin@chinadaily.com.cn