Despite recent conflicts between Venezuela's national oil company and oil giants operating in the country, a Venezuelan official stressed Monday that the country is open to foreign investment in its oil fields.

"Venezuela will continue to honor long-term crude agreements," said Alejandro Granado, chief executive of Citgo Petroleum Corp., Venezuela's U.S. refining arm.

Speaking to a conference of refining executives, Granado stressed that a number of opportunities for investing in Venezuela's Orinoco crude belt remain.

Opportunities to build a refinery to upgrade or process the heavy oil from that region in Venezuela or abroad are available, he said. The country would also welcome foreign investment in a joint venture, he said. He stressed that the country would continue to be an important supplier of crude to the western hemisphere.

In the past year, ConocoPhillips and Exxon Mobil Corp. have pulled out of the country, owing to conflict over the country's tax regime. Granado defended Venezuela's position in this conflict, saying that the country had to protect its natural resources and levee taxes to ensure their preservation. He noted that other foreign oil companies, including Chevron Corp., Statoil and, most recently, Eni SpA are operating in the region.

Granado represents Citgo, the wholly owned refining arm of Petroleos de Venezuela SA, or PdVSA. Citgo operates three refineries, which all process heavy grades of crude oil, which are difficult to refine.