Nnamdi Kanu protester
A protester holds up a picture of Nnamdi Kanu, the Biafran leader charged over comments he made about Nigeria's president Getty Images

The leader of a group seeking independence from Nigeria has reportedly apologised for comments he made about the country's president Muhammadu Buhari.

Nnamdi Kanu is the self-proclaimed leader of the Indigenous People of Biafra (IPOB) and director of Radio Biafra, which broadcasts from London.

The International Crisis Group says that Kanu was arrested in October by Nigeria's domestic intelligence agency, the Department of State Services (DSS) on sedition and treason charges.

They relate to comments in his radio broadcasts where among other accusations, he called Buhari "evil" and "a terrorist", the Punch reported, with the Nigerian newspaper adding that Kanu, said he intended to write a private letter to Buhari to express his apology to the president.

Kanu also reportedly apologised to former president Goodluck Jonathan and Igbo elders for "some uncomplimentary things" he said about them.

Newsweek contacted the DSS to confirm whether Kanu submitted such a statement, but no one was available to confirm or deny the report.

Since his arrest, thousands of people have taken to the streets of Nigeria to demand Kanu's release and independence for Biafra, which existed as a republic in southeast Nigeria between 1967 and 1970.

The 48-year-old pro-Biafran leader remains unapologetic about his demand for a Republic of Biafra. His vision of Biafra encompasses 10 whole states and parts of two other states in southern and south-eastern Nigeria.

He referred to the "incessant hardship, lack of holistic development in the socioeconomic landscape of Nigeria, lack of youth employment, corruption in high offices and economic regression."

According to Punch, Kanu submitted a statement to the DSS on October 23 in which he apologized for making the comments to Buhari in the radio broadcast on August 1.

Buhari has remained quiet on the issue of pro-Biafran protests.