Australia will build an A$11 billion ($9 billion) fleet of advanced destroyers and amphibious warships, Prime Minister John Howard said, underscoring the country’s plan to remain a key Asian military power. The purchases would transform Australia’s navy into one of the most powerful in the Asia region, with two amphibious carriers able to land more than 2,000 troops, 16 attack and transport helicopters and up to 23 Abrams tanks.“The will greatly enhance Australia’s ability to send forces in strength when required, particularly in our own region, but not restricted to our own region,” Howard told a media briefing on Wednesday.Howard said his government had agreed to buy three Spanish-designed F100 air warfare destroyers at a cost of A$8 billion, to be built in Adelaide by Australian firm ASC, US firm Raytheon RTN.N and Spanish government-shipyard Navantia.The 6,000-tonne warships will be equipped with advanced US Aegis radars and may one day carry SM 3 missiles as part of US and Japanese efforts to build a ballistic missile shield in Asia to guard against threats like a nuclear-armed North Korea.Two 27,000-tonne amphibious warships, also Navantia designs, would be built in Victoria state in partnership with Australian defence firm Tenix, with the first to enter service with the Royal Australian Navy by 2012, Howard said. The Navantia destroyers beat a larger and more costly rival US design, while the amphibious warships were preferred over a smaller French design.