NEW YORK (Reuters) - Northern Offshore Ltd said on Monday it would buy two semi-submersible drilling rigs for $750 million from a unit of Transocean Inc, which had agreed to sell the vessels to win UK regulatory approval for its purchase of GlobalSanteFe Corp.

Transocean will provide $745 million in seller financing to Northern Offshore through the end of 2010 at an annual interest rate of 10 percent.
The rigs, the GSF Arctic II and GSF Arctic IV, are currently located in the North Sea and are designed to operate in water depths of 1,200 feet and 1,500 feet, respectively.