A U.N. spokesman is calling on countries thinking of leaving the International Criminal Court to instead work within the system to improve the court.

Farhan Haq said Thursday that the U.N. is aware of reports that Philippine President Rodrigo Duterte is considering withdrawing his country from the International Criminal Court and urged them to reconsider.

South Africa, Burundi and Gambia have announced plans to withdraw and Russia, which is not an ICC member, snubbed the court with President Vladimir Putin signing a symbolic decree to withdraw.

"It's clear from what the leaders have said that there are many, many governments who believe that there's a problem. What we're saying is what you do with that is you work to improve the system," Haq said.