Brazilian oil startup HRT Participacoes em Petroleo SA (HRTP3.BR) said Wednesday that it had hired a semisubmersible drill rig from Transocean Ltd. (RIG, RIGN.VX) to drill prospects off the coast of Namibia, where the company holds stakes in 12 exploration blocks.

In a filing with stock regulators, HRT said a final contract would be signed in 15 days. The Transocean Marianas semisubmersible rig will be hired for 280 days, enough time to drill four wells, HRT said.

"We are very happy with the speed of our exploration campaign in Namibia," HRT Chief Executive Marcio Mello said in a statement.

Earlier this year, HRT said that it had started talks with potential partners to sell a stake in the company's offshore exploration blocks in Namibia. HRT expects to complete the stake sale in the first half of 2012, with more than 20 companies showing interest, Mello told Dow Jones Newswires in an exclusive interview in April.

HRT's U.S. affiliate opened a data room in Houston after recently completing a three-dimensional seismic survey of the company's holdings off the coast of the West African country. Namibia holds operating stakes in 10 blocks and minority shares in two others in the Walvis, Orange and Namibe basins.

Citigroup Global Markets was hired as a strategic adviser on the sale, also known as a farm-out.

-By Jeff Fick, Dow Jones Newswires; 55-21-2586-6085; jeff.fick@dowjones.com