Nigeria, March 15 -- In a wandering, combative and, at times angry testimony convicted warlord Alieu Kosiah laid out an argument that he and his former Ulimo ally Kunti Kamara, whose appeal of his 2022 war crimes conviction was the forum for Thursday's appearance, were innocent.

Mr Kosiah was convicted of multiple war crimes in a Swiss court in 2021.

His 2023 appeal upheld those convictions and added crimes against humanity convictions. Mr Kosiah is serving a 20-year prison sentence but could be released as early as 2027 with good behaviour. Mr Kosiah announced in the court, for the first time, that he would take his case to the Swiss supreme court and, if necessary, the European Union Court for Human Rights.

Given he and Mr Kamara are...