Israel's acting Prime Minister, Shimon Peres, today warned against attaching a "miracle-type" importance to the reconvening of the Geneva Conference on the Middle East but said he understands the political and psychological need to begin the process of negotiation toward peace.

"If we raise expectations that later we cannot fulfill we shall become the victims of our own exaggeration," Peres said in an interview."Yet the Geneva conference may fulfill both a political and a psychological need that somewhere, somehow, we start something. It is very much for that reason that Israel has never asked to postpone either the date or the idea of a Geneva conference," he said.

Asked about President Carter's recent statement that there is a consensus among Middle East nations, he said: "I can see one consensus existing in the Middle East, and it is a wish to put an end to wars and to reduce the war machines . . . I do not believe that any war has solved anything in the Middle East."

Peres said the desire to reach a "negotiated and peaceful settlement is today deeper and larger than ever before," but "We still have to negotiate a very complex set of issues."

He added that he does not believe that anybody would claim there is a consensus between Arabs and Israelis on the major issues.

Peres, who is also defense minister, took over as acting prime minister last week following Yitzhak Rabin's decision to step down because of a scandal involving illegal bank accounts in Washington.

President Carter, following his meeting with Jordan's King Hussein last week, said it would be better not to have a Geneva conference "unless we see some strong possibility for substantial achievements" beforehand. An Israeli Foreign Ministry spokesman said Israel would rather postpone Geneva than go into a conference that had not been prepared in advance.

Responding to a question seeking clarification of Israel's position of Geneva, Peres said: "I think that the Geneva conference should be put in its proper proportion - namely, that before the conference there should be informal negotiations about subject matters and the scope of the conference itself. Once we agree on that then we can go to Geneva and start negotiations."

He said that Israel would now ask to postpone a new Geneva conference, only that it be properly prepared.

Peres said that a new Geneva conference should be seen as the "opening stage" for negotiations and it should be understood that "we cannot produce miracles overnight." Going to Geneva should not be considered just a ceremonial act, but the "official and formal starting point for negotiations."

"While not wanting to exaggerate the importance of Geneva, I see no reason to belittle it, either," he said.

Although some Israelis have expressed dismay at recent statements from the Carter administration concerning a return to 1967 borders and a Palestinian homeland. Peres said he is convinced that the Americans have not formed a definite peace plan of their own and that there is a "basic understanding" that any settlement would be reached as a result of negotiations and not by imposition.

He does not consider these controversial statements to be "trial balloons" indicating a shift in American policy, he said but attempts to arrive at "concepts and definitions."

"I remain convinced of the basic good intentions of the President of the United States," Peres said. "One must remember that over the years, time and time again, the United States and Israel have been able to work out a joint strategy for peace. Under no circumstances would I give up this hope."

Part of the reason Middle East countries want peace is "the economic situation, which is like a huge dragon covering the horizon of the whole free world", he said. "It is obvious here that we shall have to deal with serious economic and social problems. I don't believe that any war has solved anything in the Middle East, including the latest one in Lebanon."

Peres said that although there might be a consensus in favor of peace in the Middle East, there is still a very wide gap between Arabs and Israelis on three major issues - the nature of peace, the price of peace, and the Palestinian problem.

Israel prefers a "complete peace without any reservations," while the Arab position is still "very qualified" on what is meant by peace, he added.

Peres referred to Israel's readiness for territorial compromises but said United Nations Resolution 242 speaks of an Israeli withdrawal from territories, not all territories occupied in the 1967 war. The English version of the resolution does not include the article "the" in front of the word territories, but the French version does. The issue has long been a contention between the Arabs and Israelis.

On the Palestinian issue, Peres said: "There is still a wide gap between us and the Arabs on a Palestinian state." Peres said that a separate Palestinian state between Jordan and Israel "would not bring real peace in the Middle East but real troubles, endangering Jordan, Israel and, in my judgment, the American position as well."