Britain and the Patriotic Front guerrillas backed away from an immediate confrontation in the deadlocked Rhodesian settlement talks today, keeping the door open for resumption of negotiations.

British Foreign Secretary Lord Carrington opened bilateral talks with the rival delegation of Zimbabwe-Rhodesian Prime Minister Abel Muzorewa on transitional arrangements leading to independence. Thus, he finally carrried out his 13-day-old threat to proceed to the second stage of the talks without the Front, which has refused to meet his condition of first accepting a British-proposed constitution.

British spokesman Nicholas Fenn was at pains, however, to emphasize that the talks with Muzorewa were preliminary, no proposals were made and no decisions taken, making it apparent that the conference would mark time for a while in hopes of Front participation.

The Front hinted broadly that a way around the deadlock would be found.

Guerrilla spokesmen said they would join the talks on transitional arrangements once they had "clarified" with Britain, the United States and other potential donor nations proposals about an agricultural fund that would assist a new Zimbabwean government in compensating white farmers for expropriated land.

Provisions in the proposed constitution calling for compulsory compensation for land and for protection of pensions are the key remaining roadblocks to agreement. The two issues combined could cost an independent government more than $2 billion.

"As far as we are concerned, negotiations will continue," a Front statement said. "We will move on to discuss the transition as soon as the question of land and compensation is clarified."

The Front was "in the process of seeking clarification from all concerned," according to the statement, although British officials said there had been no request for talks on the issue. THE U.S. Embassy declined comment on whether the Front had approached the United States on the matter.

An embassy official said the United States had informed Britain and the African front-line states supporting the guerrillas that Washington would "be prepared to cooperate in a multi-donor effort to assist in agricultural and economic development of an independent Zimbabwe within the framework of a wider development concept for southern Africa as a whole."

He added that there could be no specfic commitment and that any such effort would be contingent on a successful outcome of the London conference and on congressional approval.

Carrington made a similar, carefully phrased offer of potential help last Thursday, it remains to be seen whether it is possible to work out more specific language which would lead the Front to accept the constitution, contingent only on agreeing to the transitional arrangements leading to independence.

The guerrillas criticized Carrington's separate talks with the Muzorewa delegation, saying they "have no significance either in relation to an overall settlement or in ending the war" and added that they "jeopardize the success of the talks."

Leaders of the five front-line nations -- Zambia, Tanzania, Mozambique, Botswana and Angola -- are to hold a summit meeting in Dar es Salaam, Tanzania, Wednesday. They are expected to give the guerrillas full support, especially on the land question.

Tanzanian President Julius Nyerere said in Dar es Salaam today that the land compensation issue was the only problem and added that the crisis atmosphere at the talks "is utterly artifical."

Yesterday Shridath Ramphal, secretary general of the Commonwealth under whose intiative Britain is sponsoring the conference, sharply criticized Carrington's move to go ahead in talks without the Patriotic Front. He met today with the foreign secretary and the two agreed to differ on the issue, British sources said.

Front-line representatives in London issued a statement today supporting Ramphal. They said Carrington's acctions "jeopardized" hopes for peace which "cannot be achieved with the exclusion of the Patriotic Front."

Mark Chona, Zambian President Kenneth Kaunda's special representive at the London talks, also met with U.S.Ambassador Kingman Brewster.