Separatist leader Nnamdi Kanu pleaded not guilty to seven counts of terrorism and treason charges in a new trial in Nigeria on Friday, with a fourth judge now presiding over the case.

Kanu, a British citizen who leads the outlawed Indigenous People of Biafra (IPOB) movement, was first arrested in 2015 but disappeared from Nigeria while on bail in 2017.

He was subsequently arrested in Kenya in 2021 and charged in Nigeria with seven counts of terrorism. Kanu has pleaded not guilty.

Judge James Omotosho, the new presiding judge, set April 29, May 2 and May 6 as trial dates.

Kanu's trial has been plagued by repeated delays, judicial recusals and two denied bail applications, prompting him to seek negotiations with the Nigerian government.

Kanu Agabi, a senior lawyer who now leads Kanu's defence, apologised to Judge Binta Nyako, who recently recused herself, and to prosecutor Adegboyega Awomolo and Kanu's lawyer Alloy Ejimakor for past courtroom outbursts by the defendant.

Kanu's IPOB campaigns for the secession of southeastern Nigeria, where the majority belong to the Igbo ethnic group. Nigerian authorities have labelled IPOB a terrorist organisation.

More than a million people perished in a three-year civil war that began in 1967, the year Kanu was born when the region attempted to secede as the Republic of Biafra.