The letter appealing for the IPOB leader's release was necessary following the AGF's comments suggesting that Mr Kanu's case should be left to the courts to decide.
Nnamdi Kanu's legal team on Thursday called on President Bola Tinubu and the Attorney General of the Federation (AGF) and Minister of Justice, Lateef Fagbemi, to see to the release of the leader of the proscribed Indigenous People of Biafra (IPOB) from custody.
The team, led by Nnaemeka Ejiofor, made the appeal after delivering a copy of an appeal letter seeking Mr Kanu's freedom to the AGF's office at the Federal Ministry of Justice, Abuja, on Thursday.
"We are calling on the President of the Federal Republic of Nigeria, Bola Tinubu, who is a democrat, and the Attorney General of the Federation, Lateef Fagbemi, not to follow the steps laid down by General Muhammadu Buhari which tied Nigeria down.
"We believe that President Tinubu would do better and do the proper thing by releasing Mazi Nnamdi Kanu, not only releasing him but by releasing every human being that is called an IPOB member whether justly or unjustly detained," he said.
Mr Kanu, who faces charges of treasonable felony over his campaigns for secession of a Biafra Republic carved out of Nigeria's South-east states and parts of some neigbouring states, has been in detention since June 2021 during the former President Muhammadu Buhari administration.
He was first arrested in 2015 and held in detention until 2017 when he was granted bail by the trial judge, Binta Nyako, of the Federal High Court in Abuja.
But he fled the country following the invasion of his home at Afara-Ukwu near Umuahia, the Abia State capital, in September 2017.
Since then, Mr Kanu stopped attending trial, prompting the judge to later revoke the bail granted him and ordered his arrest.
The Nigeria government arrested Mr Kanu in Kenya in June 2021 and brought him back to Nigeria to continue with his trial.
During his first court appearance after his return to Nigeria, the judge remanded him in the custody of the State Security Service (SSS), where he has since remaind.
Why appeal for Kanu's release
Mr Ejiofor explained on Thursday that the letter of appeal for the IPOB leader's release was necessary following the AGF's comments suggesting that Mr Kanu's case should be left to the courts to decide.
The appeal letter referenced judgements from both the federal and state High Courts and the Supreme Court, all affirming that Mr Kanu's rendition from Kenya and the invasion of his residence were unlawful acts.
On 13 October 2022, the Court of Appeal in Abuja dismissed the terrorism and treasonable felony charges against Mr Kanu, citing the manner in which the Nigerian government forcibly brought back to Nigeria.
But the Supreme Court would later overturn the judgement of the Court of Appeal, ordering that his trial should continue at the Federal High Court in Abuja.
Mr Ejiofor argued that the AGF, who assumed office last year, might not have been fully briefed the whole truth regarding Mr Kanu's case.
He described his client's ordeal in custody as government persecution infringing on fundamental rights.
Call for release of detained IPOB members
Mr Ejiofor also called for the release of all detained IPOB members held in military custody in Abuja.
Also, he accused the SSS of being the primary agent responsible for the arrests and detentions of IPOB members, noting that numerous courts have ruled in favour of their immediate release.
Additionally, Mr Ejiofor said a judgement by the Enugu State High Court nullified the proscription of IPOB. He said the judgement should be respected and enforced.
"The High Court in Enugu ruled that the way and manner IPOB was proscribed as a terrorist organisation is wrong. That judgement is a subsisting one because it came after the proscription of the IPOB by the Federal High Court in Abuja.
"Under our law and jurisprudence, the ruling and judgement should be obeyed by everybody, which is the legal judgement of the High Court of Enugu State," he added.