Portland's openly gay mayor, Sam Adams, was asked to resign by a representative from the Portland Police Association over the revelation that he covered up a sexual affair with a teenage boy during his mayoral campaign.

Adams, 45, humbled himself and asked for forgiveness at a Tuesday press conference, where he admitted that his long-standing denial of having a sexual relationship with 18-year-old Beau Breedlove was not true.

“I want to apologize to the people of Portland for my dishonesty,” Adams said. “I made a mistake. This was clearly an error. I clearly messed this one one up.”

A representative from the Portland Police Association asked for Adams to resign, saying that his actions had left him at risk of “blackmail,” reports The Oregonian.

“Had they attempted to blackmail me, I would have taken the appropriate steps,” Adams responded.

Rumors of the affair surfaced in 2007 during the mayoral campaign. Adams' long-standing response has been to dismiss those reports as a “nasty smear.”

In a Thursday interview with a reporter from the Willamette Week, the mayor was confronted with evidence the newspaper had gathered over several months concerning the affair, including statements from several of Breedlove's friends who said the young man had confided in them that the two shared an intimate relationship. Adams remained steadfast in his denial.

But Monday, during a telephone conversation with the newspaper, he acknowledged the affair saying: “I want to publicly acknowledge I made a mistake and apologize for it. In the past, I've characterized my relationship with Beau Breedlove as purely non-sexual and that is not true.”

During the press conference, Adams admitted to sleeping with Bleedlove as soon as three weeks after he turned 18 and the two dated for “maybe two months.”

Adams made contradictory statements, saying he would not resign over the affair, then 20 minutes later said he would if it “was in the city's best interest.”

The mayor met Breedlove in 2005 when the former legislative intern was 17.

Adams became the first openly gay mayor to run one of the 30 largest cities in the United States when he took office on January 1.