The Movement for the Emancipation of the Niger Delta rebel group in April said it was launching a new campaign this year. More than 80 percent of the government's revenue comes from crude oil exports and groups like MEND tried to stop operations of oil companies operating in the oil-rich south.
Nigerian Petroleum Minister Diezani Alison-Madueke blamed saboteurs and vandals for the loss of about 150,000 barrels of oil per day.
"I must say that both the British and U.S. governments have been in discussions with us and are keen to join hands with us to fight this menace," she was quoted by The Guardian newspaper in Nigeria as saying.
Alison-Madueke said during a Houston energy conference oil majors were still interested in the region despite the militant activity. She said crude oil theft, however, was a professional job, with crude oil taken to foreign countries for refining.
"We are working to put in place a strategic platform that will involve us all and enable us track and fingerprint stolen crude," she said.
Nigeria is the No. 7 oil producer among the 12-member Organization of Petroleum Exporting Countries.
2014: The Year in Music [PHOTOS]