Secret plans to transform European domestic rugby union are being considered by French and English sides keen to put the professional club game on a firmer financial footing. One leading official from a Premiership club is warning of a possible "violent breakaway" by wealthier European clubs, with teams in South Africa understood to be monitoring the situation.

With a new Heineken Cup season kicking off this weekend, the Guardian can reveal that separate proposals are on the table to create a world club championship, bringing together the best eight non-international sides from both hemispheres. The champions of the Aviva Premiership, RaboPro12 and French Top 14 leagues, plus the Heineken Cup winners, would be invited to play the table-topping sides in New Zealand, South Africa and Australia, plus the Super 15 champions.

Money, as usual, is at the heart of the matter. The Heineken Cup is run by European Rugby Cup Ltd which acts on behalf of the unions involved. Tournament turnover has doubled in five years to just over €50m (£43m) but there are many who believe the competition is capable of generating far more. The 12 Premiership clubs receive only around €1m apiece for competing in Europe, although successful teams will earn more through increased sponsorship and gate revenue.

The frustrated clubs are aware the existing five-year ERC accord ends in June, although any stakeholder wishing to exit the tournament is still required to give two years' notice. All the tournament's major TV contracts expire in 2014 and Heineken's title sponsorship deal runs until 2013. The strict salary cap in England remains a further bone of contention for millionaire club owners who, despite the economic turmoil across Europe, are seeking to expand.

"From an English and French clubs' point of view the Heineken Cup is a growing competition but it is essentially controlled by the unions and played by the clubs," said a prominent club figure. "There are some English and French clubs who do not regard that as an ideal situation. There is also a growing weariness in South Africa with Sanzar [South Africa, New Zealand and Australia Rugby]. They feel they're at a playing disadvantage by constantly having to travel and, despite having more commercial pulling power, do not get a proportionally bigger share of the revenue. They feel South Africa is subsidising Australia and New Zealand, which are relatively small markets."

If Saracens' experiment of playing a Heineken Cup pool match in Cape Town in January proves a commercial success it will encourage those who believe the world's best club competition should not be restricted to six countries. A global calendar, with more rugby scheduled in the northern hemisphere summer, is on the wishlist. "My suspicion is that you're not going to get these sort of changes by consensus," the source added. "There will be a violent breakaway, probably. All the ingredients are there. If you look at the countries with maximum television rights and sponsorship potential – England, France and South Africa – they're all in the same time zone.

"Any sort of alliance between them would have serious consequences for Australia, New Zealand and the Celtic unions as well. There are certain common interests which might lead to some kind of [new] competition but there is still an awful lot of detail to be worked through."

The ramifications of any split would be enormous, not least for the Rugby Football Union and the French Rugby Federation. There will be shivers of alarm in Wales, Scotland, Ireland, Australia and New Zealand, who do not boast such large populations. A less apocalyptic scenario being pursued by Premiership Rugby, the body which represents the 12 leading English clubs, is to stage more offshore games. They believe European club rugby could emulate golf, which holds regular Tour events in Asia and the Middle East.

Mark McCafferty, Premiership Rugby's chief executive, acknowledges fixture congestion and player welfare remain major concerns but confirms a world club championship is back on the agenda: "We have ambitious clubs and we'll look to see if we can create these things. Europe has got to continue to be ambitious and push the boundaries. Sometimes we get frustrated about the pace of progress. It has come a long way in a few years but I think it can go even further.

"One of the advantages of a recession is that people realise you have to do things differently to generate interest. We're inching towards a scenario where there might be more frequent competitive matches between northern and southern hemisphere clubs, not just friendlies."

The surprise re-election of Jean Pierre Lux as ERC chairman ahead of England's Peter Wheeler has irked the bigger clubs, with McCafferty calling for a third European competition to be introduced to expand the game beyond its traditional heartlands. "We feel there needs to be a stronger form of leadership and governance within ERC. We've got to try and embrace the emerging countries: Russia, Spain, Romania, Georgia etc. The Heineken Cup shouldn't just be limited to six countries."

Others, though, insist the current formula is fine. Derek McGrath, ERC's chief executive, is a fan of Saracens' Cape Town initiative but says the existing structure is largely working. "At the moment in Europe we're probably talking to a loyal rugby audience of 30 million. We believe there's a potential loyal audience of 70 million in Europe and, clearly, a lot more globally. Rugby is back in the Olympics and there is no question that is opening doors already. But our broadcasters and sponsors are saying they want to see stability. This tournament is still on an upward curve. Our objective is for the Heineken Cup to be the most competitive tournament in the world. We want to expand our frontiers."

Leinster's chief executive Mick Dawson cast doubt on the wisdom of English and French clubs attempting to break away. "I'm on ERC's commercial and marketing committee and I know the English clubs well. I'd say the monies generated by the TV contracts are quite big and competitive. Everyone says 'You can get more money' until they actually have to go and get it. Is there a whole pot load of money out there that we're missing? I doubt it."

The Irish province, the European champions, has seen its turnover figures quadruple inside seven years under the existing format. "The thing about running away is that you need people to play against. I think the Heineken Cup is elite enough at the moment. Winning it gives you serious credibility and it's easier to sell your wares. You can't buy what it does for you."