Defense Secretary Dick Cheney, long skeptical of Mikhail S. Gorbachev's reforms, said Friday he was ending a visit to Moscow with a "very positive" impression of changes in the Soviet military and political system.

"If things continue . . . it will be possible to say that we do not consider the Soviets as adversaries," Cheney said at a joint news conference with Soviet Defense Minister Marshal Dmitri T. Yazov.Cheney, who met with Gorbachev, Yazov and other top Soviet leaders, said one sign of the change in Soviet policy was the cooperation in the Persian Gulf crisis.

But he gave no indication that he had sought or secured Soviet promises to sanction or assist possible military action to force Iraq to withdraw from Kuwait.

The U.S. defense secretary praised Soviet cooperation in bringing diplomatic and economic pressure to bear on Iraq, and said "we have not given up on that policy."

"I have also made it clear that we have not ruled out other options," said Cheney. He declined to speculate on possible U.S. military steps.

Yazov said, "If we succeed in solving the conflict with political means, it will be a great step."