Mr Kanu, the IPOB leader, is facing terrorism charges at the Federal High Court, Abuja.
Peter Obi, the 2023 presidential candidate of the Labour Party, has asked the Nigerian government to release the detained leader of the Indigenous People of Biafra (IPOB), Nnamdi Kanu.
Mr Obi, a former governor of Anambra State, stated this while speaking to reporters in Onitsha on Saturday, according to a report by Punch newspaper.
The LP candidate said there was no reason for the continuous detention of the IPOB leader given that a Nigerian court earlier acquitted him, although that acquittal was overturned by the Supreme Court.
"I don't see any reason for his continuous detention, especially as the courts have granted him bail. The government must obey the court.
"The rule of law is an intricate asset that we must cherish and live with. I use this opportunity to plead with the federal government to ensure that all those who are in similar conditions are released and discussed," he said.
"We are in a democracy, and we should not be doing things that are arbitrary and not within the law."
This is not the first time Mr Obi has publicly called for the release of Mr Kanu.
The former governor, in March 2017, asked the Nigerian government to release the IPOB leader and stop the use of force in fighting Biafra agitators.
Insecurity in South-east
Mr Obi lamented the rising insecurity in the south-east and other parts of Nigeria, saying leaders should double their efforts in tackling the situation.
He expressed fear that if nothing was done to address Nigeria's insecurity, the country might slide into a failed nation.
"It is worrisome what is happening in Nigeria with the news of killings, abductions, and other vices that have made Nigeria one of the most insecure places on the earth. In fact, it is leading to a failed nation.
"I commend the government for their efforts so far, but there is a need to do more, and all leaders must come together to join hands and fight this. In the South-east, there is a need for the governors to come together to be able to tackle it," he said.
"Even in economic agenda, I want to see the South-east governors work more closely. We want to see them come together and also bring together other groups in the zone."
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Background
Mr Kanu was first arrested in 2015 under the administration of former President Muhammadu Buhari.
The Court of Appeal, Abuja, on 13 October 2022, held that the IPOB leader was extraordinarily renditioned to Nigeria and that the action was a violation of the country's extradition treaty and also a breach of his fundamental human rights.
The court, therefore, struck out the terrorism charges filed against Mr Kanu by the Nigerian government and ordered his release from the facility of the SSS.
But the government refused to release the IPOB leader, insisting that he (Kanu) could be unavailable in subsequent court proceedings if released, and that his release would cause insecurity in the South-east, where he comes from.
The government, through the office of the Attorney-General of the Federation, later appealed the court ruling and subsequently obtained an order staying the execution of the court judgement at the Supreme Court.
Delivering judgement on the appeal on 15 December, the Supreme Court reversed the acquittal granted to Mr Kanu by the lower court and consequently ordered continuation of his trial at the Federal High Court Abuja.
The court had repeatedly dismissed Mr Kanu's applications for bail.
Meanwhile, several Igbo leaders, such as Governor Charles Soludo of Anambra State and his Enugu State counterpart, Peter Mbah, separately appealed for Mr Kanu's release. But the government ignored the requests.
