Wellington - New Zealand's billion-dollar insurance monopoly is to be opened for competition, the country's National-led government announced late Thursday.

The country's unique Accident Compensation Corporation (ACC) collects about 964,233,000 New Zealand dollars (727,009,305 US dollars) annually in levies and provides no-fault injury cover for all New Zealanders and visitors.

The Prime Minister John Key said his National party had agreed with its right-wing coalition party ACT to open up ACC's work account to competition, in return for the minor party's Parliamentary support for wider reforms to the corporation.

ACC's work account covers work-related personal injuries through levies paid by employers.

It is one of six separate accounts covering a specific group of injuries.

Key has pushed for substantial levy increases and cuts to entitlements to ACC, to improve the company's accounts. But vital coalition party support for his reforms was far from certain prior to his negotiations with ACT.

Key said that competition in ACC's work account would proceed subject to approval from an independent advisory group, although Key that both the National and ACT parties expected the advisors to recommend competition.

Opposition Labour Party leader Phil Goff said the big winners would be Australian insurance companies and the losers would be hard working New Zealanders who would pay more and get less.

Key said that did not occur when the account was opened to private competition for a year in 1998.

Labour reversed that decision when it won the general election in 1999.

Labour extended the scheme's coverage and funding throughout its subsequent nine years in government, which contributed to the company's liabilities.

ACC's liability grew by 4.8 billion New Zealand dollars in the year to June 2009.

The scheme's claim liability, or future cost of existing claims, is 23.8 billion New Zealand dollars, against current net assets of 11 billion New Zealand dollars.(dpa)