The White House yesterday denied a report in yesterday's editions of The Washington Post that the administration is considering proposing a tax on disposable bottles and cans as part of the President's environmental message to the nation.

President Carter's press secretary, Jody Powell, said he could not rule out such a tax in the future, but that it is not now under consideration at the White House. He said the only such matter being considered for the environmental message. Is whether to ask for an acceleration of a study of economic incentives for solving the solid waste disposal problem.

Also yesterday, the White House broke its silence on the latest controversy involving Air Force Gen. George S. Brown, saying Carter is pleased with Brown's "professional and competent" performance under the new administration.

Brown, chairman of the Joint Chiefs of Staff, was quoted over the weekend as ridiculing Congress for meddling in defense matters and foreign policy and as defending government spying on American citizens in a secret lecture last year.

Powell, who Sunday had said Carter had no comment on the matter, issued the President's defense of the general in response to question.

Powell said Carter "is not inclined to evaluate the general's performance based on incidents that took place in the previous administration." In a reference to Carter's problem with some of his own statements during the campaign, Powell added that the President "does have a certain understanding of circumstances in which a public figure says something and later wishes he had not."

In other developments, Carter told his Cabinet secretaries that the knew it was not easy for them to withstand the "political pressures" that resulted from administration decisions such as those to cancel certain water projects and hold down the increase in the minimum wage. But he said these decisions are necessary if he is to balance the federal budget by the end of his term.

The President yesterday als named former Rep. Bella S. Abzug of New York to head the National Commission on the Observance of International Women's Year. Former First Lady Betty Ford was among those named to the commission.

Other appointees to the commission included Jean O'Leary of New York, the co-executive director of the National Gay Task Force.

The commission will sponsor meetings on the rights and responsibilities of women and a National Women's Conference scheduled for November in Houston.