Washington's planned strategic shift to Asia will challenge existing alliances as nations try to balance strong economic ties to China with defence links to Washington, a conference heard Sunday.

Many Asian countries have major business relations with China but are also defence allies of the United States.

"The political, economic and cultural ramifications of a newly-empowered Asia are bound to impact existing security and economic relationships," Singapore Defence Minister Ng Eng Hen said at the Shangri-La Dialogue, a conference on security issues.

He cited the Association of Southeast Asian Nations (ASEAN), Australia, Japan and South Korea -- which all have China as their biggest trading partner but consider the US as the "dominant resident security power" in the region.

"This divergence of economic partnerships and defence relations will challenge existing alignments among nations," Ng told the conference, which ended Sunday. "No nation wants to be in a position to choose sides."

Addressing the conference Saturday, US Defense Secretary Leon Panetta said Washington will gradually shift its naval fleet so that by 2020 it will have 60 percent of its ships in the Pacific, up from the current 50 percent.

The decision to deploy more ships to the Pacific Ocean, along with expanding military partnerships in the region, was part of a "steady, deliberate" effort to bolster the US role in an area deemed vital to its future, Panetta said.

The move reflects US concern over China's rising economic and military might but Panetta insisted the strategy was not a challenge to Beijing.

Australian Defence Minister Stephen Smith on Sunday welcomed the US plan and said it should not impact Canberra's relationship with China.

Smith, speaking to the Australian Broadcasting Corporation shortly after his return from Singapore, said the US presence in the Asia-Pacific region had been "a force for peace and stability and prosperity since the end of World War II".

Australia will see 2,500 US Marines deployed to its north as part of the Asia strategy, a move that has rankled Beijing, but Smith said he would make clear in a visit to China this week that Canberra wanted to continue to deepen its relationship with the Asian giant.

"The point I'll make to Chinese friends is that Australia has had a growing relationship with China since we were one of the countries to recognise China very early back in 1972; we've had a growing relationship for 40 years," he said.

New Zealand Defence Minister Jonathan Coleman also welcomed the US shift.

"We do welcome the US rebalancing down to our region. We see it as providing significant opportunities for training with a like minded partner," he said at the Singapore conference.

Malaysian Defence Minister Ahmad Zahid Hamidi said Malaysia will continue work with both China and the US.

"If the purpose is to stabilise the region... we would welcome the effort taken by the US," he told AFP in Singapore.

Canada wants Singapore hub as US shifts military focus
Singapore (AFP) June 3, 2012 - Singapore said Sunday it was studying a proposal from Canada to set up a logistics facility in the city-state for disaster relief efforts, reportedly to support a US military shift to Asia.

Canadian Defence Minister Peter Gordon MacKay said in an interview with The Canadian Press that the proposal was part of Ottawa's efforts to back up the US military "pivot" towards the Asia-Pacific region, which has irked China.

"The Canadians have proposed setting up a logistics support hub in Singapore for their regional humanitarian assistance and disaster relief efforts," a spokesman for the Singapore foreign ministry told AFP.

"We are currently studying their proposal," he said, giving no further details.

MacKay was quoted as saying that the proposed deal with Singapore would resemble arrangements Canada has with Kuwait and Jamaica, which has given the country military footholds in the Middle East and the Caribbean.

MacKay is in Singapore along with other defence chiefs to attend the Shangri-La Dialogue, an annual security conference that ends on Sunday.

US Defense Secretary Leon Panetta told the conference on Saturday that Washington will shift the bulk of its naval fleet to the Pacific by 2020 as part of its new strategic focus on Asia, amid China's rising influence.

The Pentagon already plans to start rotating "littoral combat ships" -- small vessels intended for operations close to shore -- through a base in Singapore, a long-standing ally of the United States.

Speaking at the conference Sunday, MacKay did not directly refer to the proposal but stressed the need for greater global cooperation in disaster relief efforts.

He recalled that Canadian troops were among the international forces involved in the massive relief operation that followed the 2004 Indian Ocean tsunami, which killed an estimated 220,000 people.

Learning lessons from that disaster, Canadian forces were quicker to respond when a major earthquake struck Haiti in 2010, carrying more supplies with their C-17 military transport planes, MacKay said.

"We realise how critical connectivity with all of our partners, friends and allies remains to ensuring that we can coordinate responses more quickly," he said.

The Asian Development Bank in March said climate-related disasters had displaced more than 42 million people in Asia over the past two years.

The Asia-Pacific "is the global area most prone to natural disasters, both in terms of the absolute number of disasters and of populations affected", it said in a report.