The leader of the Japanese crime syndicate Yakuza has pleaded guilty in a Manhattan federal court to conspiring to traffic uranium and weapons-grade plutonium to an informant posing as an Iranian general, according to US authorities.

Takeshi Ebisawa on Wednesday admitted to trafficking nuclear materials from Myanmar, as well as narcotics and arms charges.

US authorities charged Ebisawa in February 2024 with conspiring to supply nuclear materials to Iran for potential use in nuclear weapons development.

"As he admitted in federal court today, Takeshi Ebisawa brazenly trafficked nuclear material, including weapons-grade plutonium, out of Burma (Myanmar)," said Acting US Attorney Edward Kim for the Southern District of New York.

"At the same time, he worked to send massive quantities of heroin and methamphetamine to the United States in exchange for heavy-duty weaponry such as surface-to-air missiles to be used on battlefields in Burma and laundered what he believed to be drug money from New York to Tokyo."

US authorities said the scheme was detected and stopped through international cooperation with Indonesia, Japan and Thailand.