JERUSALEM, DEC. 27 (TUESDAY) -- Israeli Prime Minister Yitzhak Rabin returned early today from a surprise public visit to Oman, the first by an Israeli head of government to a Persian Gulf state.

Rabin's meeting in Muscat with Sultan Qabus, Oman's monarch since 1970, was the latest sign of erosion in the unified wall of Arab hostility toward the Jewish state. Foreign Ministry sources here said the two leaders had agreed to open interest sections, a precursor to full diplomatic relations, in January.

Since its September 1993 accord with the Palestine Liberation Organization, Israel has experienced a kind of diplomatic coming-out after decades of isolation. Jordan this year became the first Arab state since Egypt in 1979 to sign a peace treaty with Israel, and Morocco and Tunisia agreed to open interest sections in Tel Aviv.

In September, 10 Arab and Muslim countries agreed to establish postal links with the Jewish state: Algeria, Afghanistan, Brunei, Djibouti, Indonesia, Jordan, Morocco, Oman, Qatar and Tunisia. Israeli officials predict that Bahrain and Qatar will quickly follow Oman in establishing ties.

Rabin's larger ambition, an accord with Syria, remains unfulfilled. But aides expressed the hope Monday that the end of Israeli isolation would place subtle pressure on Syrian President Hafez Assad. "All these things erode the anti-Israeli front which was there for decades, and hopefully it will not be unnoticed by Assad, who believes that all of them should stand together," chief government spokesman Uri Dromi said. "Hopefully, Assad will realize how wrong he is in being entrenched in his rejectionist position."

Israeli officials described Oman's move as significant because, as one said, "the Omanis would not do such a thing without Saudi permission." Oman agreed provisionally on the opening of interest sections during a Nov. 6 visit there by Israeli Deputy Foreign Minister Yossi Beilin, the officials said, but wanted to clear the idea first with the Gulf Cooperation Council, which Saudi Arabia dominates.

"More and more we see {movement from} Arab states that said they would not move without Syrian permission," an Israeli diplomat said. "You'll see the whole Arab world in relations with Israel and Syria staying behind."

Oman's official news agency reported the visit and quoted a source at the Information Ministry as saying its purpose was "to support the peace process and efforts to accelerate the achievement of a comprehensive and just peace in the region," Reuter said.

Oman has signaled its flexibility on Israel for several months, the first time when it permitted Israel to participate in multilateral water talks there in April. In early October, Foreign Minister Shimon Peres met with Oman's Foreign Minister Yusef Alawi Abdullah, and later that month Abdullah attended the signing ceremony of the peace pact between Israel and Jordan.