Egyptian President Anwar Sadat officially informed visiting U.S. Defense Secretary Harold Brown yesterday that Egypt will refuse to make any new concessions at next week's Camp David peace talks with Israel.

Reporters traveling with Brown were told Sadat's message had been given to Brown in private talks here and was to be passed on to President Carter Monday. Israel also has indicated it will send its delegation to the foreign minister level negotiations with no new instructions.

But Sadat said at a news conference outside his Ismaila residence that he remained optimistic about the new talks and the prospects for peace with Israel. He also said he had told Brown that U.S. military support to Egypt should be on the same level as U.S. support to Israel.

Sadat linked the request for American arms to the chaotic events in Iran and said he would use them to defend "my country, my Arab colleagues and anyone in the area against foreign intervention."

U.S. officials said Brown had informed Sadat that Pentagon experts would be sent witnin six to eight weeks to assess Egypt's military needs.

The Middle East News agency reported that Sadat appointed Prime Minister Mustapha Khalil to take on the additional post of foreign minister, which has been vacant since last September.

Egypt is the final stop on Brown's four nation tour of the Middle East.