"We are negotiating a very complex issue with a very broad cross-section of interested parties.
"The reality is, to get a season structure, we're trying to agree on a long-term international calendar that leaves space for the club competitions, the international game, keeps Rugby World Cup in its premium space and allows us to build our own domestic competitions, as well as prioritising and highlighting the Super Rugby and Rugby Championship."
Tew said the parties had made concessions over the past few months and days, but more would need to be made, if this proposal was to become reality.
"There's still a bit to be done and there will still need to be a bit of tweaking, which will mean some people giving and some people receiving," he said. "Everyone needs to leave the negotiations feeling they got something, but not everything, otherwise somebody won't be happy.
"We're dealing with a wide variety of stakeholders and I can't control what's going to happen in other places, I can only talk to our people when I get home."