Israeli Prime Minister Yitzhak Rabin ended two days of talks with President Carter yesterday with no public sign of change of his country's negotiating position on Middle East peace.

In a news conference, Rabin gave his definition of "defensible borders" - a concept endorsed by Carter Monday - as "boundaries that will allow Israel to defend itself by itself." Rabin added that "they do not coincide in any way with the kind of boundaries which existed before the six-day war" of 1967.

The United States in recent years has refused to spell out its views on the territorial basis for a peace settlement, though in 1969 then-Secretary of State William P. Rogers spoke of only "insubstantial alterations" to Israel's pre-1967 boundaries.

U.S. policy has continued to back United Nations Resolution 242, which called for "withdrawal of Israeli armed forces from territories occupied" in the 1967 war and for the right of all Middle East nations to live "within secure and recognized boundaries."

Rabin made no claim that carter backs Israel's own definition of "defensible borders." White House press secretary Jody Powell said the question of "defensible borders" was not discussed in the official White House talks, despite Carter's use of the phrase Monday.

Under questioning by reporters, Rabin maintained that "legally we have the right to negotiate boundaries" quite apart from the pre-1967 borders, which he called only "demarcation lines."

The peace plank in the political platform of the ruling Labor Party - which Rabin is currently leading in a strongly contested general election campaign - declares that "Israel will not return to the borders of June 4, 1967, which constituted an incitement to aggression."

Rabin showed some interest in Egyptian President Anwar Saday's proposal for a negotiated link between Jordan and the Palestine Liberation Organization. Rabin called this "the beginning of a move in the right direction [but] not enough, not sufficient" for Israel to accept.

"I hope that toward the middle of this year we will see what is possible and what is not possible" in the search for Middle East peace, Rabin said. He said increased Israeli military strength, growing "burdens" on some Arab countries, declining Soviet influence and increasing U.S. influence in the area are hopeful conditions, but at the same time warned against over-optimism.

Rabin and his entourage made clear they were more than happy with their official reception and particularly with greater-than-expected warmth and support from Carter.

After Monday night's "working dinner" at the White House, Carter took Rabin to the family quarters of the executive mansion to meet his daughter, Amy. There followed nearly two hours of unscheduled excursion to see the musical, "Annie."

On bilateral questions the White House said Carter in the official talks reaffirmed the U.S. commitment - made in writing by then Secretary of State Henry A. Kissinger in connection with the 1975 Sinai pact - to sell F-16 fighter-bombers to Israel. However, the number and schedule of the aircraft and Israel's strong interest in co-production have yet to be settled. Israel is reported seeking about 250 of the warplanes which, if produced in the United States, would cost close to $3 billion.

The question of Israel's overseas arms exports was discussed, with particular reference to Washington's recent veto of the sale to Ecuador of advanced Kfir fighter planes including U.S. engines. The White House said the two sides agreed on procedures to be followed to minnimize frictions in the future.