American failure to reestablish its credibility among moderate Arabs may pave the way for a reassertion of Soviet influence in the area, analysts in the Mideast say.
A recent flurry of diplomatic activity marks Soviet attempts to reestablish a foothold in the region.
The Soviet efforts are being greeted by a cautious but favorable response from moderate Arab states, hoping to increase their pressure on the United States to move swiftly and forcefully toward a settlement of Mideast disputes.
Egyptian Foreign Minister Kamal Hassan Ali, in the latest indication of the Soviet diplomatic campaign, told the Cairo weekly magazine Al Mussawer last week that Egyptian-Soviet relations have improved and that the two countries will exchange ambassadors before the end of this year.
Relations between Egypt and the Soviet Union had been declining since the late President Anwar Sadat expelled some 17,000 Soviet experts from Egypt in 1972. In September 1981 Mr. Sadat asked the Soviet ambassador in Cairo to leave the country, claiming that the Soviet Union was fueling sectarian strife in Egypt between Muslims and Christians.
The foreign minister expressed hope that the normalization of Egyptian-Soviet relations would enable Egypt to obtain spare parts for its weaponry, much of which is of Soviet manufacture.
He pointed out that bilateral trade between the two countries had increased in the past year to $450 million from $350 million. And he noted that Egypt has rehired a small number of Soviet experts to help run Soviet-built factories and that Soviet Deputy Prime Minister Nikolai Baibakov made two stopovers at Cairo airport during the past month.
The Egyptian statement came two days after Saudi Crown Prince Abdullah told the Kuwaiti newspaper Al Siyassah that Saudi Arabia should consider establishing diplomatic relations with the Soviet Union.
Cautioning that this should be done at a ''suitable time,'' Prince Abdullah said: ''I am for relations with the Soviet Union because it is a superpower.''
The Soviet Union's most overt Mideast involvement is in Syria, which is the first non-Warsaw Pact country to have received Soviet SAM-5 ground-to-air missiles. An estimated 2,000 Soviet military advisers accompanied the missiles to Syria.
On a visit to Damascus last week, the deputy chairman of the Soviet Presidium , Timorbeck Kutchuu, vowed Soviet support for Syria's struggle against ''the imperialists and the Zionists.''
Earlier in the week a special Soviet emissary was reported to have held a six-hour meeting in Tunis with PLO chief Yasser Arafat. The Palestine news agency identified the Soviet official as Alec Drininski, assistant to Foreign Minister Andrei Gromyko.
The Palestine Liberation Organization's second in command, Salah Khalaf (code-named Abu Iyad) quoted that same day as saying that last month's Palestine National Council meeting in Algiers had ''unanimously adopted'' a six-point Mideast peace plan advocated by the late Soviet President Leonid Brezhnev.
In Moscow the Soviet Union and Libya agreed in principle last week to conclude a treaty of friendship and peace.
The surprise announcement came during a visit to the Soviet capital by former Libyan Prime Minister Abdul Salam Jalloud.
The Soviet Union already has similar treaties with Syria, Iraq, and Ethiopia.
Some analysts say Libya's attempt to break its isolation in the Arab world and North Africa may complicate Soviet relations with Egypt and the conservative Gulf states.
Conservative Arab proponents of establishing relations with the Soviet Union may also be tempered by snags in the reconciliation process between Oman and Marxist-ruled South Yemen.
For the first time in 18 months, Radio Aden announced the arrival of a senior Soviet official in South Yemen last week. He was Adm. Yuri Scott, deputy defense minister and commander of the Soviet Navy.
Privately, Arab diplomats link the stalling of Oman's reconciliation with neighboring South Yemen - based on an agreement concluded last October with the support of Kuwait - to stepped-up Soviet activity in the Middle East.
But some Western diplomats say the Soviet Union ''is still reacting to events rather than instigating them.''
A well-informed Western source said: ''The Soviets are just like the Americans. They grab any opportunity that arises.''