MOSCOW — Mikheil Saakashvili, a former president of Georgia who was brought into the Ukraine government to set an example of transparency and clean government, resigned on Monday and accused Ukraine’s president of supporting corruption.

Mr. Saakashvili, who was appointed governor of the Black Sea region of Odessa by President Petro O. Poroshenko in May 2015, said he was leaving because of the central government’s unrelenting obstruction of his efforts to root out graft.

“The president personally supports two clans,” Mr. Saakashvili told a group of journalists. “Odessa can only develop once Kiev will be freed from these bribe takers, who directly patronize organized crime and lawlessness.”

In a terse statement, Mr. Poroshenko’s office said it would accept Mr. Saakashvili’s resignation once it had been submitted by the cabinet.