A source close to the Taiwan-born congressman told The Associated Press the seven-term Democrat was planning to meet with congressional leaders in Washington, D.C., on Saturday to discuss the allegation, which was reported by The Oregonian newspaper.

The source, who spoke on condition of anonymity, said any potential outcome of the talks with congressional leaders is not known.

An aide to Democratic Leader Nancy Pelosi declined Saturday to comment on Wu.

The allegation seemed to be boiling into yet another sex scandal confronting a member of Congress. It comes a month after Rep. Anthony Weiner, a New York Democrat, stepped down after getting caught sending suggestive pictures of himself on his Twitter account.

Late Friday, the 56-year-old Wu issued a one-sentence statement about The Oregonian’s report: “This is very serious, and I have absolutely no desire to bring unwanted publicity, attention or stress to a young woman and her family.”

Wu was first elected to Congress in 1998 as the first Chinese-American to serve in the US House. He’s maintained a centrist voting record but has been a leading voice on human rights abuses in China. He angered the high-tech firms in his district when he voted against normalizing trade relations with China.

Pressure was building on Wu to publicly address the allegation, and to resign if it is true.

“I’m saddened to hear this news. David owes the citizens he represents a detailed explanation,” said State Rep. Brad Witt, who is running against Wu in the Democratic primary next spring. “If this accusation proves to be true, it’s time for David Wu to resign and get the help he needs.”

Another challenger of Wu in the Democratic primary, state Labor Commissioner Brad Avakian, said Saturday Wu should resign immediately.

“I think any 56-year-old man, especially a 56-year-old Congressman, that asserts himself like this on an 18-year-old girl, has got no business serving in Congress,” Avakian said at a news conference. “There is nothing that can be explained that makes this situation right. He’s got to resign.”

Quoting anonymous sources, The Oregonian reported that Wu told senior aides that the sexual encounter last November with the young woman in California was consensual. The paper reported Facebook notes indicate she graduated from high school in 2010 and that she registered to vote in California last August.

The paper said the woman decided not to press changes because there were no witnesses and it would have been her word against Wu’s.

The newspaper said its information came from multiple sources familiar with the allegation.

The Oregonian’s report adds new troubles for a congressman who fought accusations of strange and erratic behavior during his re-election campaign last year. Seven members of his re-election campaign quit in January because of behavior that included sending a photo of himself in a tiger costume to a staff member and angry public speeches.

Earlier this year, Wu told The Associated Press that his erratic behavior last year was the culmination of a period of mental health challenges that began in 2008 as marital issues led toward separation from his wife. The couple, who have two children, separated in 2009 and divorce proceedings are ongoing.

In a 2004 re-election bid, Wu acknowledged a 1976 incident from his undergraduate days at Stanford in which he tried to force an ex-girlfriend to have sex.

Oregon’s Democratic leaders were reluctant to discuss the latest allegation on Saturday.

“We’re waiting to see what happens,” Trent Lutz, executive director of the Democratic Party of Oregon, told the AP.

The Oregonian quoted sources as saying that a distraught young woman called Wu’s Portland office earlier this year and left a voice-mail accusing him of an unwanted sexual encounter in Southern California three weeks after last year’s election.

The paper said the woman is the daughter of a high school friend of Wu’s who has donated to the congressman’s campaign.

Wu represents Oregon’s 1st Congressional District, which includes southwest Portland and suburbs in Washington County.