With an eye on the national budget, Nigeria's state oil company said it would work closely with police in an effort to tackle militant threats.

The Nigerian National Petroleum Corp. pledged to coordinate with the national police force on ways to address what the oil company said were "incessant attacks" on oil and natural gas installations in the country.

According to NNPC Managing Director Maikanti Baru, "the attacks on oil and gas facilities are taking a toll on the national budget with massive shortfalls in revenue as well huge losses in petroleum products, environmental degradation, refineries shutdown and loss of lives."

The International Monetary Fund said the downturn in the Nigerian economy was a primary contributor to contraction in Sub-Saharan Africa, adding the situation in Nigeria, the region's largest economy, was particularly difficult. One key reason for the Nigerian woes, IMF economists said, was the disruption to oil operations in the Niger Delta.

The group calling itself the Niger Delta Avengers said its fighters on Tuesday took out an oil export pipeline in Nigeria operated by Chevron. The NNPC boss in response called on police to enhance its protective actions around such facilities, saying his company was ready with whatever assistance it could provide.

Police, he added, are working on "a number of strategies" to protect infrastructure in some of the hard-to-reach parts of the oil-rich Niger Delta.

The Nigerian petroleum company said it lost out on hundreds of thousands of barrels of crude oil due to unrest and banditry during the first five months of the year.

The militant group, which surfaced early this year, is fighting for a greater share of the oil wealth from Nigeria, which is a member of the Organization of Exporting Countries. The group has been in various stages of peace talks with the government since the summer.

Total crude oil production last month was around 1.52 million barrels per day, according to secondary sources, which was about 7 percent higher than the previous month, though still about 20 percent less than it was last year. A budget, meanwhile, from the government in Abuja is based on production of around 2.2 million bpd.

On Thursday, U.S. supermajor Exxon Mobil said it made a discovery off the coast of Nigeria it said contained as much as 1 billion barrels of oil.