Exxon Mobile country manager Jeff Simons said a bore hole in the Atlantic Ocean in an area claimed by Venezuela has produced positive results though he declined to discuss specifics about what had been found.
"We have found hydrocarbons but we are still evaluating to see to what extent it is in commercial quantities," Simons said. "We do not want to go too far down the road at this point. We will know after the testing and evaluation are done."
Natural Resources Minister Robert Persaud planned to meet with company officials and discuss the find.
Decades of exploration in Guyana have yet to locate a viable source of oil or gas despite the proximity of energy-rich Venezuela and Trinidad and Tobago.
Venezuela has long claimed about two-thirds of Guyana's territory as well as the offshore area where Exxon Mobil began drilling in March.
In October 2013, the Venezuelan navy detained an oil research vessel operating under contract for U.S.-based Anadarko Petroleum Corp. Guyana Foreign Minister Carolyn Rodrigues-Birkett said in March that the country would push ahead with exploration in the area despite protests by the Venezuelan government.