WASHINGTON (Reuters) - Breaking his long public silence, Rep. Gary Condit acknowledged on Thursday that he had a "close" relationship with missing intern Chandra Levy but the California Democrat said he had nothing to do with her disappearance.

"We had a close relationship. I liked her very much," Condit said in an interview with ABC's "Prime Time Thursday." But despite repeated questioning he refused to reveal whether the relationship was sexual.

"I've been married 34, years, I've made some mistakes in my life, I'm not a perfect man. But out of respect for my family and out of request, a specific request from the Levys, I will not go into the details of Chandra Levy at all," Condit said, repeating a similar statement three times during the course of the 30-minute interview.

The mystery of Levy's disappearance in April and the nature of her relationship with the married 53-year-old congressman has riveted America and sparked huge media coverage, with some drawing parallels to the scandal involving former President Bill Clinton and a White House intern, Monica Lewinsky.

The congressman is now fighting for his political life, facing calls from local newspapers and some politicians for him to quit. Police have repeatedly said, however, that he is not a suspect in the Levy case.

Asked in the ABC interview why he would not give a direct response to the questions about whether he and Levy had had an affair, Condit said: "I'm entitled to try to retain as much privacy as I can. The Levys are entitled to retain as much privacy on behalf of their daughter as they can. I'm going to honor that."

Asked whether he and Levy were in love, Condit said: "Well, I don't know that she was in love with me. She never said so. And I was not in love with her." He said they never discussed a future or having a family together.

In response to questions from ABC correspondent Connie Chung, Condit said he knew nothing about the disappearance of the 24-year-old Levy, who was last seen on April 30.

Condit said the last time he saw Levy was at his apartment on April 24 or 25 and the last time he spoke to her in a telephone conversation was on April 29.

Asked if Levy had been upset about anything, Condit said: "We never had a cross word. It was simply about her travel plans, that she was talking about going back to California. She was real excited about going through her ceremony at USC. So she was real upbeat."

Condit said he tried to call Levy again on April 30 or May 1. Asked if he had been concerned that she did not respond to his message, Condit said: "I was concerned that she had not called me back. But also just assumed that she had taken a train. And she told me the train was going to take four days." Levy had been preparing to return home to California when she vanished.

Asked if he knew whether Levy was pregnant, Condit said: "I have no reason to think that."

Chung led off the interview with a series of simple, direct questions that gave Condit the opportunity to declare his innocence in the matter of Levy's disappearance:

"Congressman Condit, do you know what happened to Chandra Levy?"

"No, I do not."

"Did you have anything to do with her disappearance?"

"No, I didn't."

"Did you cause anyone to harm her?"

"No."

"Did you kill Chandra Levy?

"I did not."

Police have questioned Condit four times and said repeatedly that the congressman is not a suspect in Levy's disappearance and that there was no evidence that a crime had been committed.

Condit said he was "puzzled" and "confused" by criticism that he had impeded the investigation by not being more forthcoming early on. "I don't think there's anyone in Washington, D.C., who's been more cooperative in this investigation than myself," he said.

Condit also said that he had not asked anyone to "be silent about anything," adding that "anyone who says that we tried to keep people from cooperating is just lying."

Condit, a married father of two, denied that he lied to the young woman's mother when she asked him whether or not he had had an affair with her daughter.

"I never lied to Mrs. Levy at all. I'm sorry if she misunderstood the conversations," Condit said. "My role was to listen, to be helpful. I knew they (the Levys) were going through pain and anguish. And I was doing everything that I could do to be helpful to them, and not be a problem."

Asked how this has affected his family, Condit said "My family's intact." He said for the Condits it was minor compared to what the Levys are going through. "Sympathy and our hearts go to Dr. And Mrs. Levy. Not the stuff that we've gone through."

Condit said in a letter distributed to his constituents on Thursday, ahead of a television interview, he had cooperated fully with police trying to find Levy.