Dungannon Swifts chairman Keith Boyd says he fears northern clubs could be killed off if Danske Bank Premiership sides accept an All-Island League proposal.
The Swifts, along with Cliftonville, were the only two top-flight sides not to place their signatures on a letter sent to Irish FA chief executive Patrick Nelson requesting input from Uefa regarding an All-Island format.
A new suggestion from Dutch media group Hypercube and the AIL Working Group has sparked considerable debate but the Irish FA remain strongly opposed.
The proposal involves Irish League sides playing 22 games before a split, with the top six then progressing into an All-Island League along with the top eight League of Ireland teams to compete for the King of the Island Cup.
Boyd believes only three Premiership teams - Linfield, Glentoran and Larne - could be confident of a long-term future if the plan goes ahead.
"The Irish League needs to watch what it wishes for. You could have an All-Ireland League with two northern teams in it and that's it," said Boyd.
"I disagree with the All-Island proposals and that's my opinion.
"The letter is about Uefa looking at it but I don't believe it is financially sustainable.
"In my view, only three of our clubs - Linfield, Glentoran and Larne - could survive in that environment. We won't be in it. Simple.
"I thought the Setanta Cup was brilliant and we were able to enjoy it, it was something different than the league.
"An All-Ireland League would involve significant travel and that costs money.
"Our league has been going strong and we have four European places to fight for next season.
"The IFA won't go for it. If the rich get richer this game will go back to the bad old days. We went to Windsor with a 16-year-old keeper (Conner Byrne) and drew with Linfield. That tells me this league is exciting.
"Clubs are right to make decisions that suit them and it's hard enough at the minute for clubs like ourselves to generate money. Where will the big crowds come from? Our club has lost in the region of £30,000 compared to last year and the lack of sponsorship is a concern. How can I go to businesses and ask them for money?"
Crusaders vice-chairman Mark Langhammer, who has highlighted a lack of investment in the domestic game by the Irish FA, said: “An All-Ireland League is nobody’s ‘silver bullet’ but it does address the fundamental sustainability weaknesses of the domestic game.”
Irish FA president David Martin stated last month: “It has been the position of the IFA, since October 2019, that we were not prepared to go down the road of an All-Island League and that hasn’t changed. We’ve made that very clear.”
The Irish FA have declined to comment on the letter sent by the 10 clubs.
Boyd, meanwhile, called on the Irish FA and Northern Ireland Football League to make a swift decision on a start date for next season.
“We are waiting on news of next season and I’d like to see more urgency from the Northern Ireland Football League and Irish FA,” added the Stangmore Park chief.
“Institute have an appeal in and it should have been heard. Things are being held up when we need to have a starting date for next season.
“I have respect for Institute but a line must be drawn and we need to plan ahead.
“My players are calling me every week but we don’t have a date. All they have to do is give us a date, subject to government guidelines.
“The clubs have responded with their preferred options but we are still waiting on clarity. As long as fans can return to grounds we can get up and running. Clubs simply won’t be open for business otherwise.
“I also don’t think any fans should be admitted into the Irish Cup final. How do you work out who is allowed to go and who isn’t? People will be arguing over tickets.
“It’s the same with the Northern Ireland game in September.”
It’s been confirmed that the registration period for signing new players in professional football in Northern Ireland will run from August 1 to October 5.
The Irish FA made the announcement, with details regarding the mid-season registration period to be confirmed.
Uefa have called on all member associations to adopt a harmonised end date to the summer transfer window this year.
• Kyle Cherry has signed a new two-year contract with Carrick Rangers.