Nigeria's oil production surpassed 1.8 million barrels per day (bpd) last month, with current average output at 1.78 million bpd, the head of the country's upstream regulator said on Monday.

The West African country, Africa's largest oil producer, relies on crude oil for nearly two-thirds of government revenue and over 80% of foreign currency earnings, making production gains critical for stabilising its economy.

But widespread oil theft, unrest and years of underinvestment curtailed output and strained public finances before Nigeria stepped up a crackdown in the oil-rich Niger Delta region.

Gbenga Komolafe, chief executive of the Nigerian Upstream Petroleum Regulatory Commission, told delegates at an energy conference that the output increase, largely possible due to the step-up in security operations, is part of a push to boost oil production by 1 million bpd to 3 million bpd.

Oil output last reached 1.8 million bpd in November.

Komolafe said the commission would continue working with stakeholders to sustain production gains and improve industry transparency.