However, the Government insisted it is ready to "facilitate" such a joint venture should it be agreed.
Carter's report said the Government considered a number of commercial partnerships for Channel 4 to secure its future funding, "some of which are still being considered" by Channel 4.
However, the Government ruled out direct financial assistance to the broadcaster "given current public service priorities", arguing that it could "alter the ethos" of Channel 4.
It also ruled out a partial privatisation of Channel 4 - either by facilitating a merger with a rival such as Five or by selling off stock on the markets. It concluded this option "could not be assured of delivering" the broadcaster's "policy objectives" over the long term.
The Government also took the view that a straight asset transfer from the BBC to Channel 4 in whatever form - a transfer of the BBC's digital assets to Channel 4 has previously been mooted in press reports - would have had "significant competition implications".
And on the subject of a merger between BBC Worldwide and Channel 4, the Government concluded that "further work is needed to be done by both the BBC and BBC Worldwide on the practical and strategic implications of further structural separation".
However, the report welcomed the two parties' joint venture discussions, which it said centred on "digital channels, advertising and DVD sales".
The report concluded: "The Government welcomes this work and believes that such ventures have the potential to deliver significant value to both parties.
"We have made clear to both parties that we are ready to facilitate such joint ventures if commercial terms can be agreed, with the appropriate approvals within the parties' governance arrangements and any relevant regulatory clearances."
Separately, the Government said it intends to update Channel 4's remit with the aim of "recasting Channel 4 for a Digital Britain".
The Government will consult on a remit that requires Channel 4 to:
- invest in a wide range of "original, innovative, high-quality audiovisual content, including film, which provides alternative perspectives and reflects the cultural diversity of the UK".
- provide audiovisual services and programming "that can stimulate learning and that will inform, challenge and inspire people, particularly older children and younger audiences".
- maintain a strong commitment to "distinctive national and international news and current affairs".
- enable through partnership, the development and reach of other public service content from British cultural organisations.
- develop new services and applications to support its overall role, "embracing the potential of all digital media to connect with audiences in new ways".
.jpg)
.jpg)