The U.S. government identified 14 companies owned by the Libya’s National Oil Corporation on Tuesday in another effort to isolate the regime of Moammar Gadhafi. The asset blocking of the National Oil Corporation by the Treasury Department is intended to prevent Gadhafi from employing the related companies in order support his part of the ongoing conflict in Libya. Last month, President Barack Obama imposed sanction on $30 billion in Libyan assets last month.

The latest action of the Treasury makes the companies subject to executive order by President Barack Obama. The sanctions bar American companies from doing business with Libyan state-owned entities in the hopes it will crimp funding for Gadhafi.

The companies, according to the Treasury are Arabian Gulf Oil Co., Azzawiya Oil Refining Co., Brega Petroleum Marketing Co., Harouge Oil Operations, Jamahiriya Oil Well Fluids and Equipment, Mediterranean Oil Services Co., Mediterranean Oil Services GMBH, National Oil Fields and Terminals Catering Co., North African Geophysical Exploration Co., National Oil Wells Drilling and Workover Co., Ras Lanuf Oil and Gas Processing Co., Sirte Oil Co., Zueitina Oil Co. and Waha Oil Co.