Former White House deputy chief of staff Michael K. Deaver, responding to criticism of his lobbying contacts with government officials on behalf of foreign and domestic clients, said last night he has done nothing improper and will change nothing in the operation of his firm.

Deaver, appearing on the Public Broadcasting System's MacNeil/Lehrer NewsHour, said he had been careful to avoid illegality and impropriety since leaving the White House. He implied that much of the criticism arises because he is doing a good job in his new profession.

"I wonder what people thought I was going to do when I left the White House? Be a brain surgeon? That lobbying was my business. That was the business I went back to," Deaver said.

Deaver, who helped set up a public relations firm in Los Angeles in 1974, joined the Reagan administration in its first term. Since returning to private life last May, he has been one of Washington's most visible lobbyists, garnering numerous clients for Michael K. Deaver & Associates, including the governments of Canada, South Korea and Saudi Arabia and a big defense contractor, Rockwell International.

A long-time friend of President and Nancy Reagan, Deaver was asked last night by Jim Lehrer whether that relationship was part of his success.

"There's no question that Ronald and Nancy Reagan are very dear friends of mine and have been for almost 25 years," Deaver said. "What I'm saying is . . . I wouldn't tread on that friendship on behalf of a client. And frankly, I'm insulted that people think that's all I have to offer."

It was reported last week that Deaver raised eyebrows around the White House when he met with James C. Miller III, director of the Office of Management and Budget, on behalf of Rockwell's effort to continue manufacturing B1 bombers after the first 100 are completed in 1988. A Rockwell competitor, Northrup Corp., wants the B1 dropped in favor of its bomber, the Stealth.

Officials said that Deaver had not violated the Ethics in Government Act, which prohibits former officials from influencing their former agencies, since the OMB is not directly a part of the White House.

But the Miller visit sparked a storm of criticism, including a call yesterday by New York Times columnist William Safire for a special counsel to investigate Deaver.

Deaver sloughed off Safire's criticism, saying, "I haven't done anything that would require a special prosecutor that I know of." He also scoffed at the Safire headline -- "Reagan's Billy Carter," a reference to former president Jimmy Carter's brother, who got into several embarrassing scrapes.

"Well, I'm not making beer," Deaver said.

Deaver said he realized that he would be a high-profile figure in his new job and took pains to avoid conflict.

"I'm very careful because I knew when I left the White House that I would be the target of interest for a lot of people, both in the media and outside the media," Deaver said. "So I hired me a very fine law firm here in Washington, D.C., and I said I want to do everything within the law. So I never make an appointment with anybody connected anywhere near the White House without checking first with my own counsel to be sure it's appropriate."

He said his law firm told him the meeting with Miller was appropriate and "they told me it's not illegal."

Deaver, in answer to a question, said he would change nothing about his operation.

He also said his influence is overstated.

"If I had the kind of access that's being reported that I had, why would I ever waste my time with a guy like Jim Miller?" he said. "Why didn't I pick up the phone and call the president of the United States and say, 'Buy some more B1 bombers?' . . . . I don't have that kind of access. I've never done that nor would I ever do that."