Prime Minister Menachem Begin of Israel has issued a stark ultimatum on the explosive issue of West Bank rule:
Accept the Israeli interpretation of autonomy for the Palestinians on the West Bank and in the Gaza Strip (which Israelis know virtually all other interested parties have rejected as far too narrow and limited). If you do not, we shall have no alternative but to go ahead with the outright annexation of the territories.
At least that appears to be the message taking shape from recent utterances by spokesmen for Begin's government--from his new and very political hard-line ambassador in Washington, Moshe Arens, to his foreign and defense ministers, Yitzhak Shamir and Ariel Sharon.
There is no bluffing in the warning. Mr. Begin has never wavered in his conviction that the West Bank--Judea and Samaria as he calls it--is Israel's by biblical right. And as long as that thinking dominates any Israeli government, Israel is unlikely to relinquish ultimate control of the territory, which it seized in the six-day war of 1967.
The message is directed not simply to the 1.2 million Palestinians of the occupied West Bank and Gaza.The quasi-ultimatum is intended also for the ears of the Egyptians, formally engaged with the Israelis in negotiations to implement the Camp David accords, which provide for ''full autonomy'' for the Palestinians.
And beyond that, it is a message addressed to the Reagan administration in Washington (which explains why Ambassador Arens got into the act) and to the West Europeans, who are again shaking a warning finger at Israel from this week's European Community (EC) summit in Brussels.
The Israeli crackdown on the West Bank from mid-March onward is (in Israeli eyes) the next step needed to facilitate either acceptance of Israel's interpretation of autonomy for the West Bank or its outright annexation. That interpretation stops short of self-government and would keep control of land and water in Israeli hands.
To implement its plans, the Israeli government has decided that it must first force a showdown with the Palestine Liberation Organization (PLO) for influence among Palestinians in the occupied territories - a showdown in which guns will be used if necessary. Already the Israeli security forces have opened fire in response to stone-throwing and tire-burning by protesting Palestinians. Five of the latter have been shot and killed since the beginning of last week.
But beyond the security forces, vigilante groups of Israeli settlers on the West Bank are beginning to use guns against Palestinians. And the ''tame'' Palestinians willing to cooperate with the Israelis through so-called village leagues are being armed and taught self-defense by the occupying authorities.
The Israelis are funding and encouraging the village leagues as an alternative to the PLO or PLO-sympathizers on the West Bank. They hope to discuss and implement the Israeli version of autonomy with these village leagues.
It was the Israelis' summary dismissal of three elected West Bank Palestinian mayors deemed pro-PLO that sparked the latest wave of protest. With the mayors out of the way, the Israelis are hoping that West Bankers will increasingly rally to the village leagues. Till now, most Palestinians expressing themselves tend to dismiss the league leaders as quislings.
But having embarked on its campaign to smash PLO influence on the West Bank, the Begin government can hardly turn back without giving the appearance of weakness. After its most recent meeting March 28, the Israeli Cabinet announced that its policy on the West Bank and in Gaza ''will continue without demur.''
Mr. Begin and his colleagues have timed their moves carefully and profess themselves confident that the policy will succeed. Behind this confidence lies their knowledge that Egypt is inhibited from any action (other than verbal protest) by its determination not to give Israel any excuse to renege on the commitment to withdraw from the last swath of occupied Sinai April 25.