"The position of the Nigerian government is that the Boko Haram terrorism has been degraded and defeated. The real Boko Haram we know is defeated," the presidency said in a statement late Tuesday.

It said the country was now facing "a mixture" of Boko Haram remnants, criminal groups and militants from the Maghreb and West Africa fuelled by turmoil in Libya and the collapse of the Islamic State caliphate in the Middle East.

"As a consequence of these international gangs, we have seen an increase of trans-border crimes and the proliferation of small arms in the Lake Chad Basin area," the statement said.

President Muhammadu Buhari, a former general who vowed to crush Boko Haram when he became president in 2015 for his first term in office, has previously said the group were "beaten".

The uprising began in northeast Nigeria in July 2009 when fighting between the hardline group and government forces left hundreds of militants dead, including leader Muhammad Yusuf.

Since then, the bloody campaign has killed some 27,000 people, displaced over two million people and spilled over into neighbouring countries.

In 2015, the Nigerian army forced the militants out of major towns but they remain at large in remote strongholds.

Fighters still launch persistent attacks and a breakaway faction loyal to IS, the Islamic State West Africa Province (ISWAP), has ratcheted up assaults against the military since last year.

Over the weekend an attack by the Boko Haram group headed by long-time leader Abubakar Shekau killed 65 villagers close to the regional capital Maiduguri.

The army has often been criticised for failing to safeguard local communities, with vigilante groups stepping into the void left by the authorities.

But the presidency said it was looking to bolster its military capacity and expected the long-awaited delivery of Super Tucano turbo-prop warplanes from the United States "beginning next year".