While dodging media scrutiny at home, Mr Tinubu submits to foreign media in London where he tried to defend Buhari's failure in the area of insecurity.
The presidential candidate of the All Progressives Congress in the 2023 poll, Bola Tinubu, has said the West is not yet comfortable with the Buhari administration, a reason he said there are not enough military weapons to "completely" overcome Nigeria's security challenges.
Mr Tinubu, who spoke to foreign broadcaster BBC after his appearance at the Chatham House London on Monday, said that the Buhari APC administration had "degraded but not completely eliminated" Boko Haram terrorism.
While Mr Tinubu submitted himself to BBC for an interview in Lonon, he has continued to dodge media scrutiny at home.
Before Muhammadu Buhari came to power in 2015, Mr Tinubu said, there were 17 local governments and four states where "foreign jihadists" had their flags, referring to Boko Haram. "That is no more," he said.
Although Nigeria has made significant gains against Boko Haram in the North-east, Boko Haram splinter group ISWAP has apparently established cells in other regions where they have claimed attacks.
For example, they were responsible for the July Kuje prison attack in Abuja and the Niger State government has publicly spoken of the terrorists' presence in the North-central state.
In addition, the North-west region is facing unprecedented insecurity with thousands of people killed and kidnapped by terrorist groups, locally called bandits. Untamed by the APC's Buhari administration, the bandits have caused massive forced displacements, while they extract criminal revenues from poor Nigerians in rural areas of the region.
Critics also blame Mr Buhari for mismanaging the IPOB secessionist agitation in the South-east, which has now become a sort of an armed insurgency.
'I will defend him'
However, despite Mr Buhari's failure in the area of insecurity, a key campaign promise in 2015, Mr Tinubu said, "I will defend him" and proceeded to make a point about the degradation of Boko Haram in the North-east. He did not acknowledge insecurity in other parts of the country.
In his defence of the Buhari administration, he said Western nations were not selling arms to Nigeria.
"Lethal weapons, ammunition, and technology, equipment that could have helped accelerate the decline of the (... ) The West is yet to feel comfortable enough to sell us arms," Mr Tinubu said.
Since under Mr Buhari's predecessor Goodluck Jonathan, Washington has expressed concerns about human rights abuses in Nigeria's conflict situation, informing their policy against arms sale to the West African nation.
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But despite state-backed abuses under Mr Buhari, including the 2015 Zaria massacre, the Oyigbo massacre of 2020, the Lekki shooting of 2020, and the massive killing of IPOB secessionists in 2015/2016 by the Nigerian security and defence forces, Nigeria has recently successfully sealed significant arms deals with the US.
Last year, Abuja took delivery of 12 Tucano jets sold by the Americans. Then, in April 2022, Washington approved a nearly $1 billion weapons sale to Nigeria after American legislators had put a hold on the deal over concerns about possible human rights abuses by the Nigerian government.
'Volunteer army'
Asked if he thought the Western arms policy toward Nigeria would change if he is elected president in 2023, Mr Tinubu said, "It could change, it might not change but we have to look at alternatives and that is mass recruitment of individuals in a volunteer army to really clean up ... "
The APC candidate had previously in Kano suggested mass recruitment of young Nigerians into the military.
'I am different'
Asked why Nigerians should vote for him after helping Mr Buhari to power in 2015, Mr Tinubu said, "because I am different; I am Bola Tinubu. I have governed in Lagos. I have built a modern state that could be a country on its own."
He added: "Buhari has done his best. I can't run away from him being my friend, my leader in the party."
Mr Tinubu mainly faces opposition from veteran presidential hopeful Atiku Abubakar of the Peoples Democratic Party and Peter Obi of the Labour Party.
