Rosneft oil production unaffected despite cyber attack,

Russia's top oil producer Rosneft (ROSN.MM) said on Tuesday its servers had been hit been a large-scale cyber attack, but its oil production was unaffected, Reuters reported.

"The company's servers underwent a powerful hacking attack," the company said on Twitter. "The hacking attack could lead to serious consequences, but the company has moved to a reserve production processing system and neither oil output nor refining have been stopped."