Jordan, traditionally a close ally of the United States, confirmed today the purchase of Soviet air defense equipment and said deliveries would begin early this year. It also said it was trying to buy new weapons from Britain and France.

The long-expected announcement of the deal with the Soviet Union, believed to involve shoulder-held ground-to-air missiles for use against low-flying aircraft, was made last night by the Army chief of staff, Gen. Sharif Zeid bin Shaker, in a speech to military academy graduates.

Neither Shaker nor the official Army spokesman today, however, provided details of the type, quantity or cost of the hardware involved.

After a visit to Moscow by Shaker last August, Jordan's King Hussein reportedly told U.S. officials of his decision to buy more Soviet air defense arms.

The agreement with the Soviets followed Hussein's refusal last March to buy the Stinger, the most advanced U.S. shoulder-fired ground-to-air missile. Hussein rejected the plan after Jordan encountered intense opposition from the American Jewish community and supporters of Israel on Capitol Hill.

Restrictions applied by the United States in the 1970s on Jordanian use of the normally mobile Hawk air defense missiles, limiting them to fixed sites, also had prompted a Jordanian purchase of Soviet materiel. Hussein said in 1981 that his country had purchased 20 batteries of vehicle-mounted SA8s and 16 batteries of ZSU23/24 rapid-firing antiaircraft cannons from Moscow.

Despite Jordan's refusal to provide details on the latest purchase, observers expressed doubts that it had bought more sophisticated Soviet equipment. They noted Hussein's longstanding reluctance to have Soviet military advisers stationed on Jordanian soil, as would be required if more advanced air defense weaponry were involved.

Since Hussein's outspoken criticism of Washington's Middle East policy last year, both the United States and Jordan privately favored Western Europe -- rather than the Soviet Union -- as a major arms supplier in lieu of the United States.

In recent years Britain has supplied Jordan with Chieftain tanks and France with Mirage fighter-bombers.

Britain, France and other western governments have sent arms-selling delegations here in recent months, and Shaker said yesterday that "Jordan is looking to conclude more deals with Britain and France in order to support our forces and strengthen military structure despite our limited resources."