The Palestine Liberation Organization today opened a General Assembly emergency session on Israeli occupation of Arab lands with a sharp condemnation of the "Camp David conspiracy" and a warning that events are 'at the point of explosion."

The special session was called at the iniative of the PLO, in an attempt to generate an international consensus for prompt and unconditional Israeli withdrawal from all occupied territories and the creation of and independent Palestian state.

Farouk Qaddoumi, who heads the PLO's Political Department, set the tone in the opening session by saying that this is the "last chance" to peacefully settle the question. He assailed President Carter and his two of his political rivals -- Ronald Reagan and John Anderson -- for opposing establishment of a Palestinian state on the occupied territory. He called on the international community to come up with an alternative to the Camp David peace process.

The alternative Qaddoumi prefers is described in a draft resolution, which already has been revised to satisfy Soviet obections to Assembly interference in the peacekeeping prerogatives of the Security Council. Arab League officials said they were prepared to modify it further to win the backing of the Western Europeans.

The text goes beyond previous resolutions on Palestinian rights by setting a deadline -- Nov. 15 -- for Israel to "withdraw unconditionally from all the occupied Palestian and other Arab territories, including Jerusalem, occupied since June 1967."

It further authorizes Secretary General Kurt Waldheim to "establish the necessary U.N. machinery to arrange, supervise and confirm the withdrawal of Israel," and to eventually "hand over the evacuated Palestinian areas to the Palestine Liberation Organization."

The Arabs maintain that this resolution, unlike those adopted by regular Assembly sessions, would be legally binding. A Security Council resolution calling for Palestine statehood, which also would have been binding, was vetoed by the United States in April.

Emergency sessions are convened under a 1950 resolution designed to transfer to the Assembly some of the peacemaking and sanctions powers vested in the Security Council if the Council is blocked by a veto. No vetoes are allowed in the Assembly.

It is this concept that has made the Soviets nervous, since the last emergency session was convened in January and overwhelmingly condemned the Soviet invasion of Afghanistan.

The first emergency special session in 1956 produced the U.N. Emergency Force in the Sinai.

The United States and Israel have questioned the legality of the emergency session on the ground that no immediate threat to peace exists, and the Israelis already have taken the precaution of informing Waldheim that any resolutions adopted will be "equally illegal and tainted."

Israel and the United States are scheduled to address the Assembly Wednesday, but American officials have made clear their determination to press ahead with the Camp David process, whatever emerges here.

"The session is unconstructive in that it is another effort to rig the record of the world organization, and damaging because the Arabs tend to get bound up by their own legislative history," one American official explained.

He recognized that the Arab resolution will get the necessary two-thirds vote in the Assembly, even without Western European support. And he said that the militancy of the text "makes it difficult for those supporting a PLO role in negotiations" -- a reference to the nine Common Market members -- "to press their case."

One of the Western European ambassadors shrugged off the exercise by saying that it would simply "increase the preception in the West that the U.N. is a fantasy world out of touch with reality. But it won't matter a tuppenny damn in the peace process because it will be ignored by all the participants -- including, if they see fit, the PLO."

There is no prospect that the "U.N. machinery" called for in the resolution -- a euphemism for a peacekeeping force which the Soviets object to being named -- will actually be set in motion.

But American officials are worried by Arab threats that once Israel rejects the resolution the move will be made to oust the Israelis from the regular fall session of the Assembly by rejecting the credentials of the Israeli delegation. A precedent for such an action was set six years ago when the South African delegation was ejected.