Celtic and Rangers have accused the Scottish Premier League of not doing their homework in proposing to launch their own subscription-based television channel.

The Old Firm effectively scuppered plans for SPL TV when they abstained at a Monday morning meeting due to award contracts for the new project.

But they have denied claims that they have already entered into separate negotiations with Sky TV or attempted to win a greater share of the television cash.

The two great Glasgow rivals took the unusual step of issuing a joint statement after the meeting and pointed out that they had initially been supportive of the idea.

"Fundamentally, our decision not to support the current proposal is based on the incompleteness of information available, the high level of business risk attached to the project that is not adequately addressed and a lack of firm substantiation of the plan assumptions," it said.

The Old Firm complained that:

• Assumptions of subscriber numbers (250,000) are optimistic.

• There is no provision for dealing with the financial consequences of any shortfall.

• Insufficient clarity is available in relation to subsequent liabilities to creditors should the channel fail as a commercial enterprise.

• The business plan does not pass the appropriate due diligence tests expected for a project of this type.

• There is uncertainty about the safeguarding the media rights of all the Premier League clubs, including the Old Firm, in the event of the channel failing.

• The control and voting rights structure for the management of the SPL channel is inconsistent with the majority voting rights contained in the SPL constitution.

Celtic and Rangers claim that the independent advice sought by the SPL and provided by accountants KPMG endorses the Old Firm reservations about the viability of the plan.

The Old Firm had written to the SPL last week but say their concerns had not been allayed.

"Also, our requests for alterations to the proposal and clarification of SPL rules to address the safeguarding of media rights have not been dealt with," said the statement.

"Therefore, the directors of Celtic and Rangers are unanimous in their view that to support the proposal in its current form would be inconsistent with their responsibilities as company directors.

"It was an appropriate course of action to assess the feasibility of SPL TV.

"But, on the basis of the findings presented, the Old Firm do not believe it would be commercially wise to proceed at this stage."

The statement added: "The apportionment of income for each of the media rights negotiated collectively by the SPL was agreed by all clubs last July.

"The Old Firm has not sought to change this agreement.

"The Old Firm has not been party to discussion with Sky or any other media company on the subject of an Old Firm channel as a substitute for or a competitor to SPL TV."