Put a celebrity behind a Washington microphone and the world tilts ever so slightly toward the ridiculous. Elizabeth Taylor testifies about money for AIDS research on the Hill and, when her former husband Sen. John Warner drops by, treats the audience to a scene of drawing room comedy combined with political satire. Robert Redford talks about oil leasing rights in the Bering Sea and the Interior Department elevators buzz with giddy employes hoping for a glimpse of the blond bangs.

"I'll pass, Mr. Chairman -- I'm in charge of the defense budget," Warner said yesterday morning when Sen. Lowell Weicker turned the questioning of the witness over to him, even though Warner is not a member of the Appropriations subcommittee that held the hearing. Earlier, both Weicker and Taylor had criticized the Reagan administration ld,10 sw,-2 sk,2 for attempting to cut funds for basic medical research while adding to the defense budget. Warner is a former secretary of the Navy.

While the audience of about 50 members of the press chuckled and snapped pictures of a smiling Taylor, Weicker turned to the observers and joked that he and Warner had been discussing "a possible transfer of $100 million" from the defense budget.

"Let's work it out later," Warner said, and, nodding toward Taylor, added, "And don't send the lobbyist to see me."

After the laughter and convulsion of camera shutters had subsided, Warner continued. "Although she is coming to lunch, and you . . . gents are invited."

"John," Taylor said as she rose to leave, "we'll talk later."

Taylor was testifying before the labor, health and human services, education and related agencies subcommittee in her role as national chairman of the American Foundation for AIDS Research.

"Since my friend Rock Hudson died of AIDS last year I have worked with the American Foundation for AIDS Research as well as community organizations across the country," she said in a soft voice nearly lost in the noise of almost 30 camera shutters whose clicks and whirs gave the impression the hearing room was filled with a colony of locusts.

"I have become familiar with the tragedy of AIDS and acutely aware of research funding needs . . . It is my hope that history will show that the American people and our leaders met the challenge of AIDS rationally and with all the resources at their disposal, for our sake and that of all humanity."

In addition to the press and subcommittee staff, Taylor's audience consisted of Sen. Arlen Specter (R-Pa.), Sen. Mark Andrews (R-N.D.) and Andrews' wife Mary, who had come to see the subcommittee at work.

"I haven't seen anything like this in the 30 days we have had hearings," Weicker said of the press coverage as he welcomed "Elizabeth," who wore a red suit and a hairdo that resembled a towering helmet of black and white spun glass.

"Given the choice between beauty and power," Weicker said, "I'd rather have beauty."

In the afternoon, in another room packed with cameras, Redford appeared at the Interior Department with leaders of the oil and fishing industries, environmental groups and Alaskan native organizations to present to Interior Secretary Donald Hodel a proposed compromise plan for the federal government's Alaskan offshore oil and gas leasing program.

Redford is the founder and president of the Institute for Resource Management (IRM), a nonprofit organization he described as "a mechanism to deal with the issue of balance, of what we're going to preserve and what we're going to protect."

During a press conference, Redford recalled his introduction to the world of celebrity spokesmen. Twelve years ago, he studied and then criticized a western power plant. "When I spoke up," he said, "things got quickly distorted. I learned the difficulty of speaking out depending on who you are . . . I was burnt in effigy. It was said, 'What does he know? He's an actor.' "

The Reagan-era audience laughed, as did Redford. "Well, things have changed since then," he said.

Over the past 10 months, IRM has held discussions with the leading groups involved with Bering Sea development. The participants came up with a map outlining areas to be included and excluded in the Department of Interior's five-year leasing program. Redford and others called the negotiations revolutionary, given the traditional antipathies of the participants and the complexity of the issues, and said the results bode well for future negotiations on other environmental-development hot spots.

"My interest is certainly for environmental protection, but not at the cost of economic growth or development," said Redford.

And then he was done. William Johnson, president of the Standard Oil Production Co., took the podium.

"Okay," he said to the crowd. "You can give your cameras a rest."

And they did.