With little advance notice, former Portland Mayor Sam Adams on Friday left his job as director of the U.S. branch of a D.C.-based environmental think tank.

His departure from World Resources Institute comes one month after former mayoral staffer Cevero Gonzalez alleged that Adams made sexually inappropriate comments in the work place, drank heavily and behaved erratically. Willamette Week first reported Adams' departure.

Adams told The Oregonian/OregonLive in a text Wednesday that he had been thinking about leaving for a while. He said his decision to leave is not related to Gonzalez's allegations, which he called false.

Leaving the job now "is a natural inflection point in terms of the work flow," Adams said.

He provided an email he sent World Resources Institute Employees Monday. He touted what he called a "wonderful whirlwind three-years," during which the group created and grew the United States program that he headed.

Adams informed World Resources Institute management last week that he planned to leave, according to a statement by the institute's communications director, Michael Oko.

"Sam's departure is not due to sexual harassment nor allegations made by Cevero Gonzalez," Oko wrote.

Adams, 54, served as mayor of Portland from 2009 through 2012. Allegations that he was romantically and sexually involved with a teen while serving on the City Council went public just weeks into his term, diminishing his power. Then Oregon Attorney General John Kroger decided not to prosecute the former mayor after the teen gave contradicting statements, but Adams chose not to run for a second term.

Adams would not say what he plans to do next.

"I have some options," the former mayor wrote. "Stay tuned."

--Jessica Floum

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