Oil futures climbed on Friday, with U.S. prices ending at their highest in more than 13 years, as Russian’s invasion of Ukraine, and Western nations’ sanctions on Moscow in retaliation, threaten to disrupt global crude supplies. Oil prices have been “a one-way market, but the potential return of Iranian crude supplies could provide much relief to this very tight market,” said Edward Moya, senior market analyst at OANDA.

News reports said Iran and world powers were close to an agreement to restore the 2015 nuclear deal, which is expected to lead the U.S. to lift sanctions on Tehran, allowing more oil to flow into the global market.

Data from Baker Hughes on Friday, meanwhile, revealed the first weekly decline in active U.S. oil-drilling rigs in six weeks, implying a slowdown in output.

West Texas Intermediate crude for April delivery rose $8.01, or 7.4%, to settle at $115.68 a barrel on the New York Mercantile Exchange. That was the highest front-month finish since September 2008, according to Dow Jones Market Data. For the week, prices rose 26.3%, the largest percentage climb since the week ending April 3, 2020.