Melbourne, Dec.29: Australia may need to double the size of its submarine fleet to counter threats posed by rival submarine outfits in the region, particularly from countries like India and China, said the country’s former defence minister Kim Beazley.

Beazley’s comments come after The Australian this week revealed that incumbent Defence Minister Joel Fitzgibbon had ordered planning to begin on the next generation of submarines to replace the six Collins-class boats when they are retired in 2025.

Beazley also called on Prime Minister Kevin Rudd’s Government to urgently tackle what he said was a "glaring weakness" in Australia's anti-submarine warfare capabilities.

Beazley said the strategic scenario facing Australia had changed and that a larger submarine fleet was needed.

"I think we need to have up to 12 submarines because of the numbers of submarines being developed elsewhere," The Australian quoted him, as saying.

The 17-year submarine replacement plan will be the longest and most expensive defence project undertaken in Australia, potentially costing up to 25-billion Australian dollars.

It comes at a time when the navies of countries like China, India, Malaysia, Pakistan, Indonesia, Singapore, Bangladesh and South Korea are planning to acquire modern, conventional submarines.

Beazley believes that six submarines would no longer be sufficient to combat this regional growth or protect the navy's new surface ships from enemy torpedoes.

Fitzgibbon has said the new submarines will be built in Adelaide and all options remain open in relation to the design and the capabilities of the boats and the weapons they will carry.

Studies will begin immediately within Defence, with the aim of winning "first pass" approval for the design phase from cabinet's National Security Committee in 2011.

Although Defence will examine the option of nuclear submarines, Beazley said Australia should opt for diesel-powered vessels. (ANI)