Jonas Savimbi, leader of pro-western guerrillas fighting the Soviet-backed government of Angola, offered yesterday to drop plans to attack U.S. oil companies operating there if they stop "lobbying" against his movement in the United States.

In an interview with Washington Post editors and reporters, Savimbi, who heads the National Union for the Total Independence of Angola (UNITA), charged that Chevron/Gulf in particular is "making a lobby here against me."

"If they don't want to get hit, they don't make politics," he said. "If they stop lobbying, then we are prepared to re- consider our stand."

Chevron/Gulf spokesman Charles G. Wootton said the company has no position on U.S. aid to UNITA and has decided not to be drawn into the aid debate. "We're not lobbying the issue," he said. "We're staying out of politics."

He did say, however, that company representatives spoke to members of Congress last November to explain "our story" that "American property and lives" were at stake in the war and "to please consider that as well."

Last week, Savimbi attacked Chevron/Gulf and other American oil firms during several news conferences for providing Angola with funds to pay for the estimated 35,000 Cuban troops backing its war against UNITA and $2 billion worth of Soviet arms that the United States says Angola has purchased over the last two years.

When UNITA will attack oil installations of Chevron/Gulf's Gulf subsidiary is a matter of "strategy" and "timing," Savimbi said.

Sunday, he said UNITA had already begun attacking Gulf pipelines but denied that it had played a role in an abortive attempt by South African commandos last May to blow up those installations. The commandos carried UNITA leaflets.

Savimbi has come to Washington seeking U.S. political backing and military aid, specifically antitank guns and antiaircraft missiles. His warnings about targeting U.S. oil firms as part of UNITA's strategy have created a new complication in the Reagan administration's quest for congressional backing of its plan to provide Savimbi with covert military and other aid.

During yesterday's hour-long meeting, Savimbi also said:

*UNITA condemns South Africa's apartheid system and, if it takes power, would not establish diplomatic relations with that nation, presently its main military backer, until the South Africans abandon the system.

*UNITA has been receiving "very substantial support" from several Arab countries in addition to South Africa, and "even the French with a socialist government" never stopped providing arms, training and "what I need."

*UNITA realizes no military victory is possible in its struggle and seeks an accommodation with Angola that would provide for an interim transitional coalition government for as long as three years before elections are held.

*UNITA now controls 80 percent of Angolan diamond-mine production and has been contacted by de Beers Consolidated Mines of South Africa, which holds a 52 percent interest in the Angolan mines, regarding sales and marketing issues.

Proceeds from diamond sales provide UNITA with funds to maintain offices abroad and pay its public relations firm here of Black, Manafort, Stone and Kelly.