Former president Gerald R. Ford yesterday eliminated himself as an "active" candidate for the 1980 Republican presidential nomination and urged his supporters to work for other candidates.

"I urge those who may have held back to ascertain my intentions, to jump into the fray in behalf of the candidate of their choice," Ford said.

Ford has repeatedly said he is not a candidate for the nomination and did not expect to become one, but yesterday's statement, made to reporters in the House press gallery, went further than those past statements.

Ford himself characterized the statement as more "definitive" than others.

Ford said he had made a "firm decision not to become an active candidate." He added he would not permit anyone else to enter his name in a primary or state contest.

He did not close the door on a draft, but admitted the likelihood of a "brokered convention is very remote."

"I would reconsider my position only if my party felt it was essential for me to do so or if onforeseen circumstances developed," Ford said. Asked what those circumstances might be, Ford said, "I don't know. You define it."

Ford associates believe it would take the unexpected collapse of Ronald Reagan's campaign to bring the former president into the race.

Ford denied he was pressured into the decision by other Republican leaders.

"This was totally done by myself," he said. Asked if his wife, Betty, had pressed him not to run, Ford said, "Betty and I always had a working relationship" but added it was basically his decision.

Early assessments of Ford's announcement, mostly from Republicans who oppose Reagan, were that it would help the candidacies of the more than half dozen Republicans trying to overtake the former California governer.

Rep. Guy Vander Jagt (R.-Mich.), chairman of the Republican Congressional Campaign Committee, said potential supporters of George Bush, Sen. Howard Baker (Tenn.), former Texas governor John Connally and others "may have been holding back waiting for a possible candidacy by Ford. To the extent that someone might emerge from the pack, this gives them a better shot at emerging."

Reagan, who was in the Capitol yesterday to meet with about 35 Republican members of the House and Senate, said Ford's statement was "consistent with what he has been saying."

"If there are some out there who have held off committing themselves, they will now probably make up their minds," he said.

While Ford denied pressure in making his decision, he was bluntly told two weeks ago in a breakfast meeting with Republican House and Senate leaders that his toying with a possible candidacy was helping Reagan and making it difficult on other candidates.

Vander Jagt said House Republican leaders, many of them old friends of Ford from his years in the House, told Ford, "Either do it or don't. But don't keep tantalizing people."

Ford made his announcement on short notice, suddenly appearing in the House press gallery, accompanied only by Secret Service agents and aides.

Asked about the timing and locale, Ford, who rose to minority leader during his 25 years of service in the House, said, "The House of Representatives is an old home and I thought this would be an appropriate place to make the announcement."

Ford said he made the decision a week ago when he saw that he would be coming to the Capitol to receive from the House Administration Committee a presentation of two bound volumes of his campaign speeches.

While many House Republicans were at the presentation, they claimed to have no prior knowledge of what Ford was going to do.