A Syrian prospect shuttered by war was characterized Friday by Gulfsands Petroleum as the "most important asset" in its portfolio.

The company announced in January 2012, nearly 10 months after Syria's civil war began, that it discovered an oil and natural gas reservoir in the country with an estimated 19.2 million barrels of oil equivalent. One month later, it decided to halt operations in an area dubbed Block 26 and elsewhere because of sanctions imposed on the Syrian government.

Gulfsands said at the time it was "disappointing to be obliged" to halt operations following 2012 successes and the exploration potential left in the area.

"Syria Block 26 remains the company's most important asset," the company said in its most recent statement. "It must and will continue to be the company's highest priority to do all possible to ensure the security of this asset pending a return to operations in Syria."

The company, which has headquarters in London, was working in Block 26 under a joint venture with Chinese exploration and production company Sinochem.

It's been five years since the start of the Syrian conflict. Various reports from the United Nations find chemical weapons have been used during the war and the group calling itself the Islamic State, which grew out of the civil war, has been accused of committing genocide against ethnic and religious groups in neighboring Iraq.

"It is not at present possible to predict with any certainty when such a return to operations will be possible," Gulfsands said Friday.

Refineries and other oil installations under the Islamic State's control in Syria have been targeted by international forces in an effort to starve the group of fuel supplies. The company in September said its facilities in Syria remained safe and secure.

Syria has an estimated 2.5 billion barrels of oil reserves. Revenue losses from the energy sector because of war are more than $20 billion.