A group of nonaligned nations, joining in the condemnation of Israel's raid on an Iraqi nuclear reactor, called on the United States today to halt military and economic assistance to Israel as punishment for the bombing.

The communique adopted by the 95-nation group at a meeting this morning followed the general lines of a draft resolution prepared by Iraq for submission to the Security Council, which is debating the Israeli attack. This was expected, as the nonaligned group has long agreed with the Arab line on Middle East issues.

Negotiations on the resolution continued behind the scenes as more than a dozen nations addressed the council, adding their voices to the 30 that have already condemned the Israeli raid over four days of debate.

No vote is expected before Thursday.

In the council debate today, Israeli representative Yehuda Blum strongly criticized the French and British for proposing yesterday that Israel pay reparations to Iraq.

"Did the Allies pay reparations after they destroyed the Nazis' atomic plants at Peenemunde during World War II?" Blum asked rhetorically.

"Let me assure this council that Israel will pay precisely the same sum as what those who made this bizarre suggestion paid after World War II, and not one brass farthing more."

In the backstage talks, Western diplomats said they made clear to Iraq that they could not go along with its proposed call for sanctions against Israel, and urged the Iraqis to modify their resolution. Some Western and Arab officials suggested that President Reagan's press conference remarks today, viewed here as pro-Israeli, might make it more difficult for Iraq to agree to a minimal resolution limited to a condemnation of Israel.

At the close of the meeting, Iraqi Foreign Minister Saadoun Hammadi read a statement from the Islamic Conference that did not specifically renew an Arab call for sanctions. The statement said the Islamic Conference requests "that the internationl community take the measures envisaged in the [U.N.] charter to prevent Israel from pursuing such action in the future." It did not elaborate on those measures.

Although the new statement appeared to modify the Arab demands, it was not expected to be accepted by the United States, and Iraqi officials did not say whether Iraq was backing away completely from the call for sanctions.

The Arabs were looking to an American statement in the Security Council as a signal of Washington's intentions toward Israel. But after announcing that she would speak today, U.S. representative Jeane Kirkpatrick later decided to defer her speech until Wednesday.

One reason, her aides said, was her wish to get clearance from Secretary of State Alexander M. Haig Jr., who was in China. The text had already been seen by the White House and State Department.