King Hussein of Jordan, citing "a new atmosphere" of acceptance in Washington, said yesterday his government intends to ask to buy U.S. weapons "in the near future."

Defense Secretary Casper W. Weinberger, appearing in a separate interview on the same television program, said he believes Jordan needs a mobile air-defense system, but he was noncommital about the Reagan administration's likely stance on a Jordanian request for the missiles.

He said no formal request had come from Hussein, and the administration had neither made a decision nor consulted with Congress on the matter. "Without a request coming in, why, we don't have anything before us to consider," Weinberger said.

Reports that the United States is preparing to sell advanced weaponry to Jordan have created a furor in Israel, which remains in a technical state of war with the Arab nation. The Reagan administration has attempted to allay Israeli fears by noting that Jordan had not requested any such weaponry.

In the past, "Washington gave . . . a cold shoulder" to Jordan's requests for advanced weapons, Hussein said on "This Week with David Brinkley" (ABC, WJLA). That response, he said, forced Jordan to turn to the Soviet Union for its weapons, most recently by spending $200 million for 20 batteries of mobile SA8 missiles.

The Soviet sale is final, Hussein said, but he added that Jordan is still interested in buying American-made mobile Hawk ground-to-air missiles.

Weinberger discussed the sale of F16 fighter jets and mobile missiles to Jordan during a visit there last month. The defense secretary and other Pentagon officials have been looking for ways to strengthen U.S. ties to nations in the Middle East, Persian Gulf and Africa.

Weinberger's display of understanding, buttressed by recent warm meetings in the United States "with the president and many of my friends," Hussein said, is indicative of "a new atmosphere" regarding a possible arms sale.

Israeli Prime Minister Menachem Begin has said that any such weapons sale to Jordan would violate a "categorical" promise made by Reagan in September to maintain Israel's "quantitative and qualitative" military superiority in the Middle East.

The Israeli parliament backed up Begin by overwhelmingly approving a resolution condemning any such arms deal.

But Hussein said yesterday that Jordan's ability "to play a constructive role" in maintaining "security and tranquility" in the Middle East has been undermined by "the growth, beyond all doubt and reason, of Israel's might."

"We have slipped behind" the Israelis in military strength, and need more weapons to correct the imbalance, the king said.

Weinberger attempted to dispel the fears of Israel, America's major ally in the Middle East, while keeping the U.S. hospitality suite open for the Jordanians.

The United States needs Jordanian and Israeli friends in the Middle East, as long as both agree to work to keep out the Soviets, Weinberger said.

What he and Hussein really talked about in Amman last month was the United States' desire to increase "the number of friends that we have, that the West has, in the Mideast, without in any way mitigating or weakening our commitment to Israel," Weinberger said.

Weinberger said the Jordanians could use some mobile antiaircraft missiles because their immobile missile sites are inadequate for air defense.

"There's no question whatever that immobile antiaircraft defense is not effective . . . . No country that I know of relies on it," Weinberger said.