A view of the Hellenic Petroleum refineries is seen at Aspropyrgos town

A view of the Hellenic Petroleum refineries is seen at Aspropyrgos town, west of Athens, February 24, 2012. Oil rose towards $124 a barrel on Friday and was heading for a fifth straight weekly gain, as concern over cuts in Iranian supply offset worries high oil prices could restrain demand. European buyers of Iranian oil have cut back on purchases ahead of a European Union embargo on imports of Iran's oil effective July 1. Some of Iran's biggest customers in Asia including China have also reduced purchases. The sign reads, "Hellenic Petroleum S.A." REUTERS/John Kolesidis (GREECE - Tags: POLITICS ENERGY BUSINESS)