Israel does no plan to go to Cairo to present answers to the Egyptian peace initiative and will instead present its own negotiating position - at least during the first phrase of the conference that is expected to begin next week, according to official sources here.

The Israeli delegation will not be instructed nor authorized to discuss military or security arrangements during the initial phase of the conference, officials said, and thus there is no plan to add a military officer to the Israeli delegation to match Egypt's inclusion of one in its delegation.

"The answers may come later," an official said, but Israel sees the initial phase of the Cairo conference as a sorting out of "all the differences between us rather than beginning with maps."

This came as a response to Egyptian President Anwar Sadat's statement yesterday that Israelis should come to Cairo with answers to his initiative in their pockets. He said that Israel should soften its negotiating position and he raised the specter of war should the talks fail.

Israel's unwillingness to get into real substance early in the Cairo talks is a reflection of the political realities here. Sadat, in his visit here, called upon Israel to make "hard decisions" and Israeli leaders, including Foreign Minister Moshe Dayan, have called for a reappraisal of Israelis stand on the location of borders. But Prime Minister Menahem Begin is committed to making no withdrawals from the West Bank and in a democracy such as Israel, any change of policy could require long debate.

Therefore it is not considered possible here for the delegation going to Cairo next week to deliver anything like what Sadat would prefer. Its job will be to explore and to hold the door open for instructions from Jerusalem.

In London, where he is on an official visit, Begin told an Israeli reporter that he would be "greatly disappointed" if Sadat retracted his pledge of no more wars.

Both Begin and Sadat seemed to agree that the Cairo conference could last a long time. "The Cairo talks are only the beginning," Begin said.

Officials here expressed puzzlement at Sadat's reported disappointment at the low level of the Israeli delegation to Cairo.

Officials said that the Egyptian invitation ocalled on Dayan to "designate" his representatives. This was taken here to mean that Cairo did not want the talks to start on the Foreign Ministry level, or higher, and so the director of the prime minister's office, Eliahu Ben Elissar, was chosen to lead the Israeli delegation.

Officials here indicated, however, that if the Egyptians wanted a higher level delegation they could have just about anybody they wished, including Dayan or Begin.

As for Sadat's raising the possibility of war should talks fail, officials here pointed out that Dayan warned on Nov. 24, in a televised interview, that Sadat's pledge of no more wars should not be seen as a "commitment to nonbelligerence" but was instead conditional on Israeli willingness to withdraw from occupied territories.

No one should be surprised, officials said, that Sadat was talking tough following the strident anti-Sadat talk by Arab leaders meeting in Tripoli and there was no reason to believe that Sadat's remarks would affect the Cairo conference.

It is clear, however, that Sadat would like to keep pressure on Israel and to bring about Israeli concessions quickly. Israel, on the other hand, wants to go into the talks slowly. The Israeli delegation plans to bring up its own peace proposals which concentrate more on the nature of peace, such as diplomatic exchanges and freedom of navigation, rahter than changes in borders.

Thus the delegation will not be empowered to discuss final borders, military lines or security arrangements during the first phase. Later, with Cabinet approval, this or another delegation may go into these crucial matters, officials said.

In Israel's view, Sadat has presented his demands - complete withdrawal to 1967 lines and a Palestinian state - and it is understood that Israel may begin with its own position of no withdrawal to 1967 lines and no Palestinian state. That is not a pre-condition but a starting point, officials said.

Meanwhile, "Cairomania" continues to sweep Israel with newspapers pouring out features on the Egyptian capital and with Israeli journalists already in Cairo.

One early arrival reported how the immigration officer at Cairo airport embraced him. Another wrote of the feelings of the switchboard operator at the Nile Hilton, as she placed her first telephone call to Tel Aviv.

The performance is highly reminiscent of the early days of Richard Nixon's opening to China when some of the best known journalists in America were reporting every trivial facet of life in China from the quality of the food to the peasant on a bicycle they could see from their hotel windows.