| GEO Business|
| Oil prices gain ground on Nigeria unrest|
| Updated at: 1429 PST, Monday, May 18, 2009|
LONDON: Oil prices turned higher Monday, rising above 57 dollars as traders kept close watch on escalating unrest in key African crude producer Nigeria.
New York's main futures contract, light sweet crude for delivery in June, gained 68 cents to 57.02 dollars a barrel. Brent North Sea crude for July rose 69 cents to 56.67 dollars.
"An escalation of violence in Nigeria is providing support (for) prices," said Dave Ernsberger, senior editorial director for Asia at energy information company Platts.