The Islamic foreign ministers' conference today moved to press Iran to resolve the U.S. hostage crisis but tempered a proposed resolution with criticism of last month's abortive American rescue operation.

The conference appeared to be having even more trouble with a resolution on the Soviet invasion of Afghanistan. Conference sources said it was likely to pass one considerably softer than a resolution approved at a special meeting here in January.

A resolution approved by the conference's political committee today called on Iran to solve the hostage crisis rapidly "in the spirit of Islamic tolerance" and asked the United States to help in reaching that goal.

But the committee, whose decisions rarely are changed by the foreign ministers, stopped short of asking Iran simply to release the hostages.

While the resolution reflected the deep concern of many Moslem nations about the detention of the hostages, conference delegates said the U.S. rescue mission complicated the situation.

"We are not in favor of any keeping of hostages, but that does not justify the American intervention against the Iranian revolution," said Libyan Foreign Minister Ali Abdelsalam Treiki in a comment typical among delegates here.

The political committee, working through the night, passed a resolution on Afghanistan after the foreign ministers ignored a plea by Afghan rebel leaders for the Moslem world to break diplomatic relations with the Soviet Union and impose economic sanctions against it for Moscow's invasion of Afghanistan in late December.

Other countries are not bound by resolutions of the Islamic conference, but its views are considered an important consideration for the superpowers in trying to develop better relations with the Third World. Attending the conference are representatives of 38 Moslem countries plus the Palestine Liberation Organization.

The resolution on the hostage crisis, called "balanced" by an official conference spokesman, included a clause added by Saudi Arabia calling on Iran to find a quick solution to the problem. Many Moslem nations fear it is increasing tensions in the area, giving Islam a bad name and diverting Iran from important domestic and international problems, including the danger to it from the Soviet invasion of Afghanistan.

Iran objected to the clause, according to a source close to the political committee, but agreed to accept it when it was amended so that it asks the United States to help make an Iranian government solution possible.

Iranian Foreign Minister Sadegh Ghotbzadeh said the United States could help gain freedom for the hostages if it released classified documents dealing with the government of the deposed shah.

While January's special meeting did not deal with the hostage question, at least six states got up in debate to scold Iran for holding the Americans.

Today, the conference political committee inserted into its resolution on the hostage issue expressions of concern over the growing U.S. and Soviet naval forces in the Indian Ocean and Persian Gulf area.

Another section of the resolution "expressed discontent" to nations that have been reported to have aided American military efforts to free the hostages in Iran. These nations include Egypt, which has been suspended from the Islamic conference, and member states Oman and Bahrain.

Earlier today, a representative of Afghan groups based both in Pakistan and Iran asked that they be recognized by the Islamic conference as the legitmate representatives of Afghanistan and be given full membership in the conference as a liberation organization like the PLO.

The Islamic foreign ministers listened to the Afghan rebels and then appeared to ignore their plea.

"Unfortunately, the conference did not do what we expected," said Abdul Rahsoul Sayaf, head of the Islamic Alliance for the Liberation of Afghanistan, who spoke to the conference's plenary session today to present the rebel's position.

Instead of giving them arms and repeating last January's condemnation of the Soviet Union, this Islamic conference appears likely to seek some political accommodation with Moscow.

The proposed resolution calls for the establishment of a commission to find some way to resolve the Afghan crisis.

The only reference to the January resolution in the current draft, sponsored by Pakistan, is one line reaffirming with no details the Islamic conference's previous strong stance.

The new resolution calls for the total withdrawal of Soviet troops without preconditions -- presumably referring to Moscow's claim that it cannot pull out its troops because Afghanistan is threatened by foreign intervention from Pakistan, China and the United States.

In another retreat from January, the resolution asks for aid to relieve the suffering of nearly 900,000 refugees who have flooded into Pakistan in the past 18 months. But it does not request material aid for the rebel fighters as the January resolution did.

Sayaf said his Afghan rebel groups have received no aid from Islamic governments and that money collected in Saudi Arabia, the United Arab Emirates and other Moslem nations appeared headed for refugees, not the combatants.