Crude oil futures rose sharply on Monday amid concern over supply.

Light, sweet crude for July delivery gained 1.21 dollars to 65. 97 dollars a barrel on the New York Mercantile Exchange.

Brent crude for July delivery rose 96 cents at 69.56 dollars a barrel on the ICE Futures exchange in London. Gasoline supplies are closely watched as the summer driving peak is around the corner. Even though gasoline prices may be higher this summer, U.S. motor fuel demand will remain strong, U.S. Energy Department predicted.

In Nigeria, the world's sixth biggest exporter of crude, about one-fifth of its daily output is still shut after a series of militant attacks. Nigeria is Africa's leading oil producer and the fifth-biggest source of U.S. oil imports.