Kenya's opposition leader Raila Odinga. Picture: Reuters/Baz Ratner

Nairobi - A Kenyan opposition politician was charged on Tuesday with treason and unlawful assembly for his involvement in the symbolic presidential "swearing in" of opposition leader Raila Odinga in a challenge to President Uhuru Kenyatta.

The charge sheet presented by police to the court in Kajiado south of Nairobi said Miguna Miguna was being charged with "being present and consenting to the administration of an oath to commit a capital offence, namely treason".

Miguna was also charged with "taking part in an unlawful assembly" and "engaging in organised criminal activity".