President Barack Obama extended his sojourn across the Asia-Pacific, visiting Australia as the U.S. foreign policy focus pivots to the region.Obama\'s Wednesday trip to Australia follows his hosting of the 21-nation Asia-Pacific Economic Cooperation summit in Honolulu, where Secretary of State Hillary Clinton had noted the 21st century will be America\'s Pacific century as the wars in Afghanistan and Iraq wind down.China\'s growing strength in the region is also a source of concern for the countries in the neighborhood.While in Australia, which is one of five U.S. security allies in the region, Obama in his meetings with Prime Minister Julia Gillard and other Australian official was expected to stress their strong political and security ties, the Voice of America reported.The Financial Times said Obama\'s visit will also take him to Darwin in northern Australia, where he will visit the new housing facility for U.S. Marines, part of an expanded U.S.-Australia security co­operation agreement.U.S. Pacific Commander Adm. Robert Willard earlier said the United States has \"a very, very tight, close relationship with our Australian friends.\"Regional security issues include the growing economic and military strength of China and its assertiveness in the South China Sea despite rival claims of other nations in the region.The VOA report quoted Australian media reports that the Obama trip will seek increased U.S. access to ports and training facilities, and pre-positioning of equipment.Willard had said the visit would help relieve some of the pressure of maintaining an effective and sustained forward-deployed U.S. presence in the Asia-Pacific region.After Australia, Obama is scheduled to visit Indonesia for the summit of the 10-nation Association of South East Asian Nations.Washington Post said in light of concerns about China, U.S. allies across Asia have been asking for help in counterbalancing potential threats in the disputed South China Sea and elsewhere.Increasing resources in Southeast Asia would also allow the Untied States to respond more effectively to natural disasters that require massive aid.\"America remains welcome in the region and ought to stay because it has many friends, influence and much potential to do good,\" Singapore Prime Minister Lee Hsien Loong said last weekend, the Times reported.