Mexican President Felipe Calderon unveiled Wednesday the country\'s first major deep-water oil field in the Gulf of Mexico, with probable reserves of 250-400 million barrels, according to dpa. \'If this parameter is confirmed, the figure amounts to a third of the annual national production of Petroleos Mexicans (Pemex),\'Calderon said at the presidential residence Los Pinos. The light-crude oilfield lies 39 kilometres south of the maritime border with the United States and 180 kilometres east of the coast of the state of Tamaulipas. Mexico\'s state-owned oil monopolist Pemex had so far only found gas in the area. Several special guests including the media baron called the worldâ€™s wealthiest by Forbes magazine - Mexican telecommunications tycoon Carlos Slim - were in attendance when Calderon described the finding as \'good news for Mexico.