Australia said Tuesday it would introduce a "premium investor visa" to give immigrants permanent residency after a year if they invest Aus$15 million (US$13 million) in the country.

The visa, available from next July, builds on the Significant Investor programme under which people who sink Aus$5 million into Australia are granted a minimum four-year visa.

"The government will reform the programme to encourage more high net-worth individuals to make Australia home," Prime Minister Tony Abbott said in a joint statement with the immigration and trade ministers.

They said the changes would "leverage and better direct additional foreign investment, while maintaining safeguards to ensure the migration programme is not misused".

The reforms include a reassessment of where the investments were made so they matched the government's "national investment priorities".

Some 436 Significant Investor visas were granted between November 24, 2012 -- when the programme was launched -- to the end of last month, according to immigration department figures.

A total of Aus$2.18 billion was invested in Australia through the programme, with 88 percent of visa holders hailing from China.

China's foriegn ministry said it was not aware of the new "premier investor visa" plans but hoped it would not be abused by corrupt Chinese officials.

   "The information you mentioned,   it's the first time I heard of it. At the 

same time, I need to point out China is ramping up its campaign on corruption," said spokesman Hong Lei in Beijing.

"We need the Australian cooperation on this. We don't want these corrupt officials or fugitives to find safe havens overseas."

Canberra also announced a review of its 457-class skilled visa programme, which was tightened under the previous Labor government amid claims of abuse by employers and disadvantage to local workers.

There will be "greater flexibility" in English-language testing and skill requirements, and a streamlining of the sponsorship and visa application process.

Abbott did not specify which industries would benefit from the 457 visa changes, but stressed they "are not a way of substituting overseas labour for domestic labour".