President Goodluck Jonathan, the southern Nigerian leader who is re-running for the top job in the national election on 28 March, claimed Boko Harem is getting weaker.
"I'm very hopeful that it will not take us more than a month to recover the old territories that hitherto have been in [Boko Haram's] hands," he said in an interview with the BBC.
Who is Boko Haram?
Boko Haram fights against Western influence in Nigeria and aims to impose its version of Sharia law in the country. The group declared an Islamic caliphate in Gwoza, along the Cameroon border, in August 2014.
Boko Haram has raided several cities in the north of the country in a bid to take control of more land.
Three states, Adamawa, Borno and Yobe, have been under a state of emergency since May 2013, due to Boko Haram's deadly attacks.
"We never expected that [Boko Haram] will build up that kind of capacity. We under-rated their external influence. Since after the civil war we've not fought any war, we don't manufacture weapons, so we had to look for help to re-equip our army and the air force."
Critics have cast doubt over Jonathan's latest statement as previous comments by the government and the army claiming victory over the terrorists were proved untrue by Boko Haram's attacks.
Jonathan's comment came as AFP reported witnesses in Bama, a town previously occupied by terrorists, said Boko Haram fighters killed their wives before engaging in a battle with the army. It is believed they killed the women to prevent them from subsequently marrying soldiers or non-believers, should the insurgents die during the fight.
The Nigerian president has been often criticised for not having stepped up the efforts to defeat terrorism in the country and find some 220 schoolgirls abducted by Boko Haram from Chibok, Borno state, in April 2014. Referring to the girls, he told the BBC: "We have not seen dead girls, that is the good news. I believe they are still alive, I believe we will get them."
Shortly after, Niger, Chad, Benin and Cameroon deployed troops to Nigeria to help the local army in the fight against Boko Haram, which recently pledged allegiance to terror group Islamic State (Isis).
Since the deployment of African Union (AU) troops, the Nigerian military has regained control of several areas held by the terrorists, whose insurgence started in 2009.