Oil prices rose on Monday, adding to last week's gains, lifted by tensions between the United States and Iran, although concerns about the possibility of weakening demand kept a lid on gains.
"We are monitoring the situation very closely and are very worried. In case of physical disruption, we are ready to act in an appropriate way," Fatih Birol told a news conference, adding that there had not been a major impact on oil prices due to the strong growth in U.S. shale oil prices.