JERUSALEM — Two years after Israel and the Palestinians signed a peace accord, Prime Minister Yitzhak Rabin's chief rival and leading opponent of the agreement has softened his opposition to the pact.

Likud leader Benjamin Netanyahu, while still adamantly opposed to the 1993 accords, has begun to signal his party's willingness to accept at least partial Palestinian self-rule in the face of certain hard facts.

Netanyahu's current public position on the self-rule accord is that if the Palestinians breach its terms, then Israel would no longer be obliged to honor it. That is a far cry from saying a Likud government would suspend the agreement.

Netanyahu also no longer urges reinstituting Israel's former boycott of Palestine Liberation Organization chairman and now Palestinian Authority head Yasser Arafat as a terrorist leader.

Instead, he lists a string of stiff conditions — deliberately left unspecific — which he says a Likud-led government would demand of any Palestinian leader.

Netanyahu's change of position is attributed to "facts on the ground" established in the two years since the self-rule accord was hammered out in largely secret negotiations in Oslo during the summer of 1993 and signed in Washington, D.C., that September.

Perhaps most pointedly, the Gaza Strip — long known as the "dagger pointed at the heart of Israel" — is no longer under Israeli administration but under Palestinian charge.

Today, few Israelis would support Netanyahu's earlier calls to suspend the accords entirely — particularly if it meant returning the Israeli army to Gaza.

And if Israel and the PLO do sign an interim agreement on Palestinian self-rule, which calls for an Israeli troop withdrawal from the major Palestinian population centers in the West Bank, there would also be little likelihood of a future, Likud-led government sending troops back to occupy Nablus, Kalkilya, Bethlehem and the other West Bank towns.

But the essential irrevocability of changes ushered in by the self-rule accord goes even deeper.

Despite Netanyahu's contention that Arafat has not properly "recognized" Israel, any future Israeli government would be bound by the letters of recognition between Arafat and Rabin that accompanied the self-rule accord.

It would thus be fruitless for any future Israeli government to cold-shoulder Arafat and the PLO, and seek other Palestinian partners, now that the PLO leadership is ensconced in Gaza, Jericho and increasingly in the West Bank.

As a result, the most important provision of the accord may be the part one often ignored by readers because it is not legally binding on the two signatories: the preamble.

It states that Israel and the PLO "agree that it is time to put an end to decades of confrontation and conflict."

Political observers discern a steady, tacit recognition of these realities beneath the Likud's rhetoric.

And they expect this important point to become more apparent once the 1996 election campaign begins in earnest.

As they fine-tune their rhetoric, Netanyahu and the right-wing opposition cite two key provisions of the self-rule accord that they say the Palestinians have failed to satisfy: abrogating the clauses of the PLO's covenant that call for the destruction of the Jewish state, and curbing terrorism.

The first contention cannot be disputed. Israeli fatalities have risen in the two years since the self-rule accord was signed.

The monitoring group Peace Watch, in a report just issued, said 149 Israelis have been killed in terror attacks between September 1993 and September 1995. A total of 86 were killed in the preceding two years, the report said.

In terms of the PLO covenant, the best that can be said in Arafat's defense is that he is reportedly trying to repeal the offensive clauses as part of the interim-phase accord that is expected to be signed this month.

As for the PLO's curbing of terrorism, this is a matter of dispute between the Rabin government and its opposition.

The right wing maintains most of the Israelis killed were the victims of suicide-bomb attacks launched by militant Islamic fundamentalists.

The Rabin government, however, cites mounting evidence of the Palestinian Authority's fight against Hamas and Islamic Jihad. That evidence, the administration contends, reflects a revolutionary change among mainstream Palestinians who are increasingly committed to long-term peace.

And as Foreign Minister Shimon Peres recently noted, there is no reason to assume that terrorism would decrease if there were no peace process.

Meanwhile, Netanyahu is still taking a hard line on the accord overall.

"Is there nothing good you can say about the Oslo agreement?" an Israel Radio interviewer asked him recently. Netanyahu refused to budge.