Oil prices were up at trading start on Monday as the U.S. weighed in, intensifying tension between Saudi Arabia and Iran, and resulted in heightened investor worries on whether secure supply from the region could be at risk.
International benchmark Brent crude was trading at $65.07 per barrel at 0640 GMT for a 1.23% gain after ending Friday at $64.28 a barrel.
American benchmark West Texas Intermediate was at $58.76 a barrel at the same time for a 1.15% increase after closing last week at $58.09 per barrel.
After drone attacks on two of Saudi Arabia's key oil facilities, Saudi Arabia and the U.S. blamed Iran, while Tehran rejected the claims.
The U.S. has now decided to send more troops to Saudi Arabia to strengthen the kingdom's air defense.
U.S. Secretary of State Mike Pompeo said Friday via Twitter that Washington has sanctioned Iran’s Central Bank and National Development Fund, "both of which finance the regime’s terrorism."
"Attacking other nations and disrupting the global economy has a price. The regime must be held accountable through diplomatic isolation and economic pressure," he said.
In response, Iranian President Hassan Rouhani said Sunday, "Wherever Americans have set foot, they increased insecurity, as it was proved in cases of Afghanistan and Iraq."
He added that he would unveil an initiative at the 74th UN General Assembly this week “to guarantee the security of the Persian Gulf and Hormuz Strait with the cooperation of regional states."
By Ovunc Kutlu