PARIS, OCT. 29 -- Soviet President Mikhail Gorbachev said today the time has come for a new Arab peace initiative to resolve the Persian Gulf crisis because under the pressure of global trade sanctions, "some signs are emerging that Iraq's leadership may be heeding the will of the United Nations."

Gorbachev said he learned in an early morning telegram from his Middle East envoy, Yevgeni Primakov, who flew to Saudi Arabia today after two meetings with Iraqi President Saddam Hussein, that "some new reflections have taken place" and that Saddam's "position is no longer the same which he held some time ago."

Gorbachev, speaking to reporters with French President Francois Mitterrand after the two signed a treaty to enhance political and economic cooperation, did not spell out what changes Primakov cited, and he noted that some contacts remain secret. But he emphasized, with Mitterrand's concurrence, that Iraq may be ready for an inter-Arab parley, possibly under Saudi Arabia's sponsorship, which he said "could be the quickest way to a settlement."

Demonstrating Soviet allegiance to the wide alliance of nations backing U.N. resolutions condemning Iraq's seizure of Kuwait, Gorbachev warned Saddam that he was "building his policy on a mistake" if he believed he could split the world community arrayed against him.

"We must not permit the Iraqi regime to hope or believe there will ever be any disharmony or weakening of decisions," the Soviet leader said.

Gorbachev, while embracing the West's firm line and denouncing the "adventurism" of Saddam, said any political solution to the conflict had to take into account Iraq's position. He said "the best thing is to deal with this man" through some kind of "Arab mechanism," because there are "now more arguments than ever in favor of solving the situation by using the Arab factor."

While characterizing military options as "unacceptable," Gorbachev said sanctions might have to be intensified to persuade Saddam that he had no choice but to abide by U.N. resolutions demanding a complete withdrawal of Iraqi troops and the release of all foreign hostages. More than 3,000 Soviets are still in Iraq, and Gorbachev said it was "amoral to use the hostages for political ends."

Mitterrand, who expressed satisfaction for the anticipated return tonight of all French hostages in Iraq, said, "We will rejoice fully only when the other hostages can return to their own countries."

He said there was full agreement between the positions of France and the Soviet Union in the gulf crisis. "We will defend the same principles and the same positions in the framework of the U.N. Security Council," he said.

Mitterrand said he could see clearly how "events are moving in a way that could lead to armed conflict." He added that the only way he could envision avoidance of war was to maintain cohesion among the five Security Council members, which also include Britain, China and the United States.

Gorbachev said Primakov's mission was "an organic part" of many common efforts, "some of which are known and some of which are secret." He would not elaborate on what Primakov heard during his encounters with Saddam, but he stressed it was important to act quickly so that opportunities for peace are not lost as tensions grow.

Gorbachev's appeal, backed by Mitterrand, for the Arab world to reach a peaceful accommodation with Saddam once U.N. resolutions are fulfilled is likely to put new pressure on Egypt and Saudi Arabia. Officials in both countries have expressed a desire to crush Saddam's military machine so that it will not pose a threat to the region in the future.

Senior French government sources said their analysis coincided with the Soviet view: that Saddam's greatest concern is his own survival and that of his regime. They said Mitterrand and Gorbachev shared the belief that a key element in a peaceful solution of the crisis lies in persuading Saddam he will not be attacked if he complies with the U.N. resolutions.

Later, according to a close Mitterrand aide, strict international controls could be applied to curtail Saddam's war-making capability, including his regime's real or potential capacity for chemical, biological and nuclear weapons. He said such restrictions would have to be part of a regional agreement including Israel and could be developed in the context of an international conference to settle other conflicts, especially the Israeli-Palestinian problem.