By JOHN M. BRODER

ASHINGTON -- Kathleen Willey, a former White House volunteer, said in a television interview on Sunday night that President Clinton forced himself on her sexually in an Oval Office encounter more than four years ago and that his lawyer later tried to sway her testimony.

The interview, on the CBS News "60 Minutes," put a vulnerable human face and an emotional voice on a story that has so far been told in dry court documents and in second-hand accounts usually attributed to nameless lawyers and investigators.

Ms. Willey's story, seen by millions of viewers of the most popular public-affairs program on American television, poses a severe public relations challenge for the president, who is fighting sexual misconduct and perjury charges in a civil lawsuit and a federal criminal investigation by an independent counsel.

Ms. Willey, 51, said she was appalled by the "recklessness" of Clinton's actions and accused him of lying about the incident in a sworn deposition in the Paula Jones sexual misconduct lawsuit.

In the president's deposition, given on Jan. 17, Clinton said he had hugged Ms. Willey and might have kissed her on the forehead. But he "emphatically" denied that there was any sexual intent in his actions.

Ms. Willey also said one of Clinton's lawyers, Robert Bennett, had subtly tried to intimidate her into not testifying or into playing down the incident shortly before she gave her sworn statement on the matter to Ms. Jones' lawyers in January. Bennett denied the accusation.

Ms. Willey's account is the first detailed accusation of an unwanted sexual advance by the president in the White House. Initially a reluctant witness in the Jones lawsuit, Ms. Willey repeated on the television program much of the story that she told in her January deposition.

It was on "60 Minutes" six years ago that Clinton salvaged his first presidential campaign, which was faltering because of accusations that he had carried on an extramarital affair with an Arkansas lounge singer, Gennifer Flowers. With Hillary Rodham Clinton by his side for that interview, Clinton denied the affair but acknowledged causing "pain" in his marriage. In his Paula Jones deposition, Clinton admitted having sex with Ms. Flowers, but only once, in 1977.

Sunday night's interview came at a similarly perilous moment, as prosecutors from the independent counsel's office investigate accusations that Clinton had conducted a sexual affair with a former White House intern, Monica Lewinsky, and then orchestrated a plan to cover it up. Even the president's supporters say that if proved true, the accusations of perjury and obstruction of justice in the Lewinsky matter could end Clinton's presidency.

Ms. Willey said she had come forward now because "I just think that it's time to tell this story."

She added: I think that too many lies are being told. Too many lives are being ruined. And I, I think it's time for the truth to come out."

A CBS spokesman said Ms. Willey had not paid been for her appearance on "60 Minutes." The program has been viewed, on average, by 20 million American households each week of this season, said the spokesman, Kevin Tedesco.

Ms. Willey added a number of new details that were not in her deposition, including her talking about the president's actions with Nathan Landow, a Maryland real estate developer and major Democratic contributor. She would not elaborate on her discussions with Landow.

Landow has acknowledged that Ms. Willey is an acquaintance but denied again on Sunday that he had tried to influence her testimony.

""My only comment to her was she should do what she feels is best for her," Landow said in a telephone interview on Sunday.

Landow is scheduled to be interviewed on Monday by FBI agents from the independent counsel's office about his dealings with Ms. Willey.

Ms. Willey also said Clinton invited her to visit him in the 1992 campaign, saying that if she came, he could "get rid of" the Secret Service agents assigned to guard him.

She said she had jokingly suggested that he needed some chicken soup because he had developed a sore throat from the rigors of the final weeks of the campaign. She declined Clinton's invitation, she said, "because my instincts told me he wasn't interested in chicken soup."

The White House on Sunday night released a response to Ms. Willey's account, repeating Clinton's denial that the incident had occurred and pointedly refusing to discuss her possible motives in going public two months before Ms. Jones' suit is to go to trial in Little Rock, Ark.

"As the president emphatically stated under oath and reaffirms today, Ms. Willey's allegation is simply not true," said the statement, issued in the name of James Kennedy, a special adviser to Charles F.C. Ruff, the White House counsel.

"As he testified, Ms. Willey asked to see him to discuss her concerns about her family and financial situation. The president sought to comfort Ms. Willey at this obviously stressful time for her. He did not touch her, and she did not touch him, in any sexual manner."

The statement continued: "Notably, over the last four years, the president and Ms. Willey continued to have a friendly relationship and he is bewildered by her allegation. He has no idea why she said what she did or whether she now believes that's what happened. As the president has testified, Ms. Willey has been through a terrible time in her life and he will not speculate about her actions."

Ms. Willey, telling her story in a halting voice but in graphic detail, said she visited the president in the Oval Office in November 1993 to seek a full-time paying job at the White House because her family was in desperate financial straits.

The president, she said, led her into a private study, embraced her and then tried to kiss her on the mouth. Ms. Willey said Clinton touched her breasts and placed her hand on his genitals, which, she said, were palpably aroused.

Ms. Willey said she felt overpowered by the president but pushed him away and said, "I think I'd better go."

She continued: "And, at the same time, I wanted to, I thought, 'Well, maybe I ought to just give him a good slap across the face.' And then I thought, 'Well, I don't think you can slap the president of the United States like that.' And I just decided it was just time to get out of there."

Ms. Willey also said she later questioned her own behavior, wondering whether she had sent inviting signals to the president.

"The only signals that I was sending that day was that I was very upset, very distraught," she said, "and I needed to help my husband."

She said she felt that Clinton had taken advantage of her in a moment of extreme personal distress. Her husband, Ed, committed suicide that day, but she did not learn of it until after the encounter with the president.

As she left the Oval Office, she said, she thought, "I just could not believe that that had happened in the office," she told the CBS interviewer Ed Bradley. "I, I just could not believe the recklessness of that act."

Ms. Willey also said Bennett, the president's lawyer, met with her before her deposition in the Jones case and said that he had just seen the president and that Clinton wanted to say "he just thought the world of me," Ms. Willey said.

Bennett then said, "Now, this, this was not sexual harassment, was it," according to Ms. Willey. She said she did not answer him.

"And he said, 'Well, and it wasn't, it wasn't unwelcome, was it?' And I said to him, 'It was unwelcome and unexpected,"' Ms. Willey said.

She told Bennett that she had intended to testify fully about the Oval Office incident and that he then said -- menacingly, in her view -- that she should hire an experienced Washington criminal lawyer.

Bennett, in an interview on the "60 Minutes" program and earlier in the day on the ABC News program "This Week," said that the president's reaction to Ms. Willey's account, first published in outline form last summer in Newsweek magazine "was one of shock, bewilderment, outrage."

He also said there was material that remained under seal in the Paula Jones suit that undercut Ms. Willey's story. But Bennett, declined to characterize it.

And he disputed Ms. Willey's account of their meeting before she gave her January deposition. Bennett said he had meet with Ms. Willey and her attorney, Daniel Gecker, and he told her that the president thought well of her.

"I said my understanding is that you were very well thought of at the White House," Bennett said on "This Week." "And the president did like Ms. Willey. And that's why he is so bewildered by what is occurring."

In what could be a sign of significant erosion in the president's support in a heretofore solid constituency, Patricia Ireland, president of the National Organization for Women, said she was deeply troubled by Ms. Willey's account.

"It's not just sexual harassment," Ms. Ireland said on the CNN program "Late Edition." "If it's true, it's sexual assault."

Feminist groups have continued to support Clinton as he confronts accusations of sexual misconduct from Ms. Jones and throughout the criminal investigation into his relationship with Ms. Lewinsky.

Ms. Ireland's remarks represent the first crack in that solid wall of support among feminists. Ms. Willey's account, if true, Ms. Ireland said, "is certainly a much bigger problem than a question of womanizing or a private sex life."