Buhari said the vandalism and oil theft carried out by IPOB is responsible for the shortfall of the daily production quota in Nigeria.
He disclosed this during a question and answer session with Bloomberg, a United States, US-based publication.
He accused the international communities of funding the separatist group.
Buhari claimed IPOB was being funded through international financial networks.
“Criminality and terrorism in oil-producing regions hamper production, and it would help if our western allies designated IPOB as a terrorist group, given their complicity in damage to pipelines and infrastructure.
“We urge those same international partners to take additional steps costing them nothing, by proscribing another group – IPOB – as a terrorist organization.
“Their leadership enjoys a safe haven in the West, broadcasting hate speech into Nigeria from London, spending millions lobbying members of the US Congress, and freely using international financial networks to arm agitators on the ground. This must stop,” he said.
Meanwhile, Buhari recalled that four years ago, the country unveiled plans for a new gas pipeline that would connect Nigeria to Europe.
“Last week (2nd June) – in record time – the Nigerian National Petroleum Company (NNPC) entered into an agreement with the Economic Community of West African States (ECOWAS) for its construction,” he added.
“On July 1st, the Nigerian National Petroleum Company (NNPC) will become a limited liability company and be subject to more robust auditing and commercial disclosure obligations.”
The president said the transition would help stimulate investment and boost transparency, where corruption has deterred the former and stymied the latter.