The communications minister Lord Carter has reiterated his support for a series of joint-venture partnerships between the BBC's commercial arm, BBC Worldwide, and Channel 4 – but has ruled out a private sector solution or a direct Government subsidy to fund a projected £150m funding gap.

Carter's Digital Britain report said that a fully-blown merger between the two organisations had been ruled out because a straight asset transfer from the BBC to Channel 4 would have "significant competition implications" .

That means executives from Channel 4 and Worldwide will continue discussions about greater co-operation with no immediate final solution to Channel 4's financial difficulties in sight.

The report also raised the prospect of alternative solutions emerging, but did not go into detail. "Alternatives to the joint ventures with BBC Worldwide have also emerged over recent months: the board of C4 is right to explore whether those make commercial sense," it said.

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