WASHINGTON (Reuters) - Some 200 U.S. Marines arrived in Australia on a six-month deployment on Tuesday, the first of 2,500 troops expected to rotate through a de facto base in the port of Darwin as part of plans to deepen the U.S. military presence in the Asia-Pacific.
The deployment of Marines to Australia was part of a deal announced late last year by President Barack Obama and Australian Prime Minister Julia Gillard to increase bilateral military cooperation and training.
"This is completely irrelevant militarily but quite important as a signal and that's why it is valued in the region," said a diplomat from the Asia-Pacific region.
Chinese officials have questioned whether the move is part of a larger U.S. strategy aimed at encircling it and thwarting the country's rise as a global power.
The first group of Marines will engage in exercises with the Australian Defence Forces and also will travel to other nations throughout the region for training and exercises, a Marine Corps spokesman said.
The force is expected to grow in size over time to become a 2,500-person Marine Air Ground Task Force, the spokesman said. It is expected to be a rotational force, with different units moving through for short periods of time rather than being based in Australia permanently.
The first 200 Marines were from the 3rd Marine Regiment based in Hawaii.
The decision to base Marines in Australia comes as the United States implements a new defense strategy that calls for a shift in emphasis to the Asia-Pacific.
China has questioned whether strengthening military alliances would help the region when economic woes put a premium on cooperation.
The port of Darwin is located 500 miles from Indonesia, putting the Marines in a position to respond quickly to any humanitarian and security issues in Southeast Asia, where disputes over sovereignty in the South China Sea have caused rising tensions.
In announcing the basing decision in November, Obama stressed that it was not an attempt to isolate China.
"The notion that we fear China is mistaken. The notion that we are looking to exclude China is mistaken," he said, adding that "we welcome a rising, peaceful China."
(Reporting By David Alexander; Editing by Bill Trott)