Tullow Oil has derailed its attempt to sell up to half its Ugandan assets in a move analysts said was a "material" shifting its plans to bring in one or two partners to help with the estimated $5 billion cost of developing its Ugandan assets.

Tullow, the U. K. explorer with the most licenses in Africa, seeks to sell as much as 50 percent of three combined blocks in the Lake Albert region.

"We weren't very keen on doing it, but we needed to do it to move the project forward at a pace. Now we can keep a higher percentage interest and deliver what the government wants", Heavey told Reuters in an interview.

The major strategy of explorers is to locate an oil field, set up the extent of the discovery, and then to sell the field to a larger company, such as Eni, which largely seeks to grab money by efficiently producing oil, rather than by finding it.

It is speculated to submit a list of preferred partners for the approval by the Ugandan government in the first week of February. The expected names on the list include Total SA and Exxon Mobil Corp., according to Goodbody Stockbrokers.

Eni to remain adamant as it disapproves to withdraw its bid for the Heritage assets until it discerns signals on the Uganda government's position on the deal.