Argentina have been invited to join New Zealand, Australia and South Africa in a new Four Nations tournament from 2012.

The competition will replace the existing Tri Nations, however Argentina will only be accepted if they satisfy conditions which include guaranteeing that their strongest side is available.

SANZAR, which comprises the New Zealand, Australian and South African rugby unions, will have the final say on whether Argentina fulfil the entry requirements.

SANZAR chief executive Andy Marinos said: "To have the Pumas, currently ranked sixth in the world, join with the three top ranked international teams in world rugby will be exciting for fans, players, sponsors and broadcasters across our four countries and beyond.

"They play a different style to the All Blacks, Springboks and Wallabies and their inclusion will see the Tri Nations evolve to be a truly southern hemisphere championship."

Australian Rugby Union chief executive John O'Neill said: "Argentina has shown commitment, passion and a work ethic to date that highlights their desire to have the Pumas playing at the highest level possible on a consistent basis.

"Australia is excited by the possibility of having the Pumas in a Four Nations Championship.

"It is important therefore, with a conditional invitation on the table, for Argentina to keep moving forward and satisfying the necessary conditions."