The Scottish Premier League is set for showdown talks on 9 December to solve the dispute that has split the country's top 12 clubs.

And BBC Sport Online can disclose that Celtic's refusal to stop broadcasting matches live on their internet site was the issue that led Hearts chief executive Chris Robinson to resign from the SPL board.

League chairman Lex Gold has written to the 12 clubs inviting them to the meeting where he is expected to issue proposals designed to prevent the 10 non-Old Firm outfits going through with their threat to resign in two years' time.

The split deepened on Wednesday when Robinson resigned citing "irreconcilable differences with fellow board members and a conflict of interest".

They (Celtic) won't show Celtic against Dunfermline without our permission Dunfermline chairman John Yorkston

He has since refused to expand on his decision, but it is believed that he had become unhappy with the SPL's decision not to take legal action to prevent Celtic broadcasting matches without a licence or to inform the other clubs of its reasons.

It is being claimed that, when the SPL was formed in 1998, it neglected to supply the Office of Fair Trading with a copy of its regulations and that this provides a loophole for Celtic to carry on without a licence.

But Dunfermline Athletic chairman John Yorkston told BBC Sport Online: "It is only one lawyer's opinion and there are other lawyers who think differently."

Yorkston also denied suggestions that the 10 clubs looking to dilute the power of Celtic and Rangers were themselves now split.

Kilmarnock chairman Stir John Orr had not resigned from the board along with Robinson.

But Yorkston said: "They had a difference of opinion on this issue, but we remain united on the need for a fairer distribution of television money and the need to move from an 11-1 to an 8-4 majority voting system."

Chris Robinson resigned from the SPL board

The other clubs fear that the need for an 11-1 majority for rule changes would allow the Old Firm to exploit the expanding internet market without sharing any of the proceeds with the SPL as a whole.

"Celtic can show action form Celtic against Celtic Reserves if they like, but they won't show Celtic against Dunfermline without our permission," said Yorkston.

An SPL spokesman refused to comment about the dispute over new media rights.

All 12 clubs have also been invited by Gold to a special meeting on 18 December to decide how to react to the resignation earlier this month of SPL chief executive Roger Mitchell.

"I remain confident that with good will on all sides these matters can be resolved to the satisfaction of all 12 SPL clubs," said Gold.