The Philippine government's top lawyer, who has been defending President Gloria Arroyo's decision to declare a state of emergency, has resigned from his post.
Mrs Arroyo issued the emergency decree in February
Alfredo Benipayo told reporters he would leave at the beginning of April, but declined to give a reason.
Justice Secretary Raul Gonzales said Mr Benipayo would join the private sector.
Mr Benipayo has been leading the legal team seeking to throw out petitions made against President Arroyo in the Supreme Court.
The petitions question her decision to issue a week-long emergency rule in late February.
Mrs Arroyo said the emergency measure was necessary to defend her government against a coup plot.
It is unclear when the court will issue a ruling on the matter, but there is speculation that Mrs Arroyo may have been dissatisfied with Mr Benipayo's efforts.