The 20-team competition is expected to involve six clubs from England's Aviva Premiership, six from France's Top 14 competition, and seven of the RaboDirect PRO12 sides will qualify.
The final place would go to the winner of a play-off involving clubs from several competitions, including a second-tier tournament that is to replace the Amlin Challenge Cup.
There is also expected to be a new third-tier competition in September, from which two qualifiers would then take part in the second-tier tournament, opening it up to clubs from countries outside the Six Nations such as Georgia, Russia, Spain, Romania, Portugal and Belgium.
It is understood that agreement is very close and, once signed, all parties can then chase a resolution between broadcasters BT Sport and Sky, both of whom have indicated a willingness to agree a compromise television rights deal.
European Rugby Cup, the governing body of the Heineken Cup, will be wound up in the summer. A replacement body will be set up, with its name and the name of the new tournament yet to be finalised. The Six Nations committee is expected to provide the basis of the new governing body, with some ERC staff retained.
One player who would hope to be involved in the competition with his new club Gloucester, Greig Laidlaw the current Edinburgh captain, is to be rested for the next five weeks following a request from the Scotland camp. Vern Cotter, the incoming Scotland head coach, and his predecessor Scott Johnson, now the Scottish Rugby Union's director of rugby, want the scum-half to be fully recovered from a gruelling season in time for the summer tour of North America, Argentina and South Africa.
The Scotland No.9 will join the Aviva Premiership side Gloucester in the summer, but Cotter wants his vice-captain ready to hit the ground running once the coach finally completes his own protracted move from the French Top 14 club Clermont Auvergne around the same time as Laidlaw calls time on his Murrayfield stint.
Laidlaw was one of Scotland's leading performers in last year's RBS 6 Nations but was decidedly off-form in this year's competition, with some pundits suggesting that Glasgow's Chris Cusiter should have been given a starting role.
Johnson said: "Greig has played a lot of rugby for both Edinburgh and Scotland this season and he's been a key figure in our leadership group. His time at Edinburgh has meant a great deal to him and he will have the opportunity to play again for Edinburgh this season. With the schedule as it stands, we're grateful to Edinburgh for supporting this move."
Edinburgh supporters have been reassured that Laidlaw, who joined the capital club in 2006, will be given the chance to say his farewells before the end of the season.
In the meantime, the club's head coach Alan Solomons will put his faith in young half-backs Grayson Hart, Sean Kennedy and Sam Hidalgo-Clyne. "The performance of the national team is of the utmost importance to the whole of Scottish Rugby, and this is will be a big year for Greig," he said. "We have very capable, young Scottish scrum-halves who will compete for the No.9 shirt next season, and will continue to get the opportunities they have handled admirably in Greig's absence."