Argentina beat France in the third-place play-off at the 2007 World Cup
The leading southern hemisphere nations are considering the possibility of Argentina joining the Tri-Nations.
The Pumas are ranked fourth in the world and have been seeking entry to an annual top-flight competition.
And Sanzar, the umbrella body for the Tri-Nations teams, has now formed a working party to look at the situation.
"The executive committee has asked a working party to perform further analysis on the viability of Argentina joining the Tri-Nations," Sanzar said.
The International Rugby Board has previously insisted Argentina's future is in the southern hemisphere rather than the Six Nations.
After finishing third in the 2007 World Cup, Argentina were awarded an increased number of Test matches, up from six to nine annually, and entry into the second-string Churchill Cup competition.
They will play two Tests against England this summer with the first match to be played at the Old Trafford football stadium in Manchester, before a return to Salta for the second.
Sanzar, which represents New Zealand, Australia and South Africa, also said it was looking at expanding the Super 14 to include geographically-based conferences.