SYDNEY (AFP) - Australia's conservative opposition unveiled plans on Thursday for a military-led response to repel boat people, branding the problem a "national emergency" after the government declared a radical new policy aimed at crippling people-smuggling.

With tens of thousands of asylum-seekers risking their lives on leaky boats to reach Australia, the Tony Abbott-led opposition said they would put a senior military commander in charge of a joint agency taskforce to deal with the problem if it comes to power.

More than 15,000 boat people have arrived so far in 2013, with the influx becoming a major policy issue ahead of national elections due by the end of November, with opinion polls suggesting Mr Abbott will beat Labor's Kevin Rudd and assume office.

"There is a national emergency on our borders," Mr Abbott said as he launched his Operation Sovereign Borders plan, a day after at least nine people died when an Australian-bound boat sank off Indonesia, the latest in a series of drownings.

"This is one of the most serious external situations that we have faced in many a long year. It must be tackled with decisiveness, with urgency, with the appropriate level of seriousness.

"That's why we need to have a senior military officer in operational control of this very important national emergency."

A three-star commander would report directly to the immigration minister, with Mr Abbott saying the scale of the problem "requires the discipline and focus of a targeted military operation".

The response comes nearly a week after Mr Rudd unveiled Labor's new hardline policy under which no unauthorised boat arrivals will be settled in Australia.

Instead, they face banishment to poverty-stricken Papua New Guinea for assessment, and will be either settled there, sent back home or shipped to third countries.

Opposition immigration spokesman Scott Morrison said Mr Abbott's proposal was drawn up after years of work with senior defence advisors and would streamline decision-making into a single command structure.

"Operation Sovereign Borders is about having a clear mission, a clear chain of command and a clear policy framework for doing that," he said, claiming that under Labor 12 separate government agencies were involved in border security.

Mr Abbott has previously announced he would instruct the defence force to turn back boats when safe to do so, while helping Sri Lanka and Indonesia, the main transit countries, to intercept vessels departing their shores.

Mr Rudd dismissed Mr Abbott's policy on Thursday as "Operation Sovereign something-or-other".

"The business of border security is a hard and tough business for any government of Australia," he said.

"Mr Abbott doesn't have an alternative, he has a three-word slogan."