Two hundred U.S. Marines from the Fox Company, 2nd Battalion, 3rd Marines are now in Darwin as part of a new bilateral defence agreement between Australia and the United States.

The 200 soldiers were welcomed by Australian Defence Minister Stephen Smith upon arrival Tuesday night at Darwin Airport aboard a charter flight. The 200 are the first of 2,500 American troops about to begin their six months tour of duty.

They will participate in joint training exercises with the Australian Defence Force (ADF) and be based at Robertson Barracks. The training exercise will be held at ADF areas such as Mount Bundy and Kangaroo Flats.

U.S. President Barack Obama inked the deal with Australia on the deployment of U.S. troops to northern Australia until 2017 when he visited the country in 2011.

Mr Smith assured residents of Darwin that there would be no problems once the soldier rotation begins. Indonesia has expressed apprehension that if the U.S. Marines would be based in northern Australia, it may inflame tensions in the Oceania-Pacific region.

The defence secretary insisted that Indonesian President Susilo Bambang Yudhoyono had earlier said that Australia, the U.S., Indonesia and the wider Asia-Pacific region including China could engage in joint military exercises.

Mr Smith and Prime Minister Julia Gillard, in a joint statement, said the arrival of the first batch of American troops is the latest in more than six decades of Canberra's alliance with Washington.

The 2,500-strong Marine Air Ground Task Force will be made up of command, ground, aviation and logistic elements, and major support equipment such as wheeled vehicles, artillery pieces, light armoured vehicles and aircraft.

"This initiative will provide tangible benefits for Australia by increasing the number, variety and complexity of training opportunities for the ADF and further developing our interoperability with U.S. forces," Ms Gillard and Mr Smith said in a statement.

"It also supports Australia's long-held strategic interests in supporting U.S. engagement in our region in a manner that promotes peace and stability. The initiative could also provide new opportunities for Australian and U.S. engagement with our partners in the region," they added.

However, the two Australian officials stressed that there are no American military bases in Australia and the situation would not change.