Lebanon today suspended military negotiations with Israel over a withdrawal of Israeli troops from southern Lebanon and said the talks would not resume until Israel released four Shiite Moslem leaders.

Lebanese Prime Minister Rashid Karami charged that Israeli soldiers on Thursday illegally detained a number of Lebanese citizens in the southern town of Sidon. In a statement to reporters following a meeting with President Amin Gemayel, Karami said it did not make sense to negotiate while the Israelis were making illegal arrests.

The suspension marked a setback for Israel's hopes of reaching security arrangements with Lebanon that would allow the withdrawal of its forces from the territory the Israelis have occupied since the June 1982 invasion.

[Washington Post correspondent Edward Walsh reported from Jerusalem that Israeli officials said that they had received no official notification of the Lebanese decision, and that there would be no official response until Israel had been notified formally of the breakoff in the talks.]

Lebanese-Israeli discussions started Thursday under United Nations sponsorship at Naqura, the U.N.'s southern Lebanon headquarters near the Israeli border. Military teams of both countries had decided to meet three times a week, beginning Monday.

Nabih Berri, the Lebanese Cabinet minister for southern Lebanon who also heads the mainstream Shiite Moslem Amal militia, said the Israelis continued to hold four out of 15 persons rounded up Thursday.

The arrests followed an attack Wednesday on an Israeli Army patrol in Sidon in which one Israeli soldier was killed and four were wounded. Israeli arrests in southern Lebanon are a common practice as the prolonged Israeli occupation has embittered Shiites there and triggered guerrilla attacks against Israeli soldiers.

Amal officials still in detention included Mahmoud Faqih, who was described by the Israelis as head of one of several Amal groups that have mounted these guerrilla attacks.

Berri called today for a general strike to protest the arrests. He stressed during a press conference that the Lebanese president and prime minister agreed to the suspension of talks and that Army officers representing Lebanon at the talks had been informed.

In Naqura, however, a spokesman for the U.N. Interim Force in Lebanon said the force had not received official notification from the Lebanese side on the breakoff of the talks.

It was not clear tonight whether the decision in Beirut doomed the negotiations, or whether it would prove to be a temporary interruption that would be overcome. It was also not clear why Israel, which had openly sought the military talks with Lebanon, chose to arrest Amal leaders at the same time the negotiations began.

Correspondent Walsh reported that an Israeli official said Saturday that if the talks are constantly delayed and lead nowhere, Israel was prepared to take "unilateral steps" in southern Lebanon to assure the security of its northern border.

This was a reference to Israel's threat to pull back from the western and central section of southern Lebanon, turning the territory over to the Israeli-backed South Lebanon Army without an agreement with Beirut.

The Israeli official said that Berri appeared to be the moving force behind the cancellation of the talks.

"From the beginning, Berri didn't want these talks," the official said. "If it was not this [the arrests], he would have found some other excuse. I think it is clear that they [the Lebanese] will use delaying tactics and will procrastinate."

In Beirut, Karami suggested the Israelis were indirectly encouraging a breakdown in security conditions in Lebanon to give themselves greater leverage at the Naqura talks. He said the Israelis could "employ it as blackmail" in the withdrawal negotiations.

The Naqura talks were arranged through the mediation of the United Nations and are part of a two-track negotiating process that Israel hopes will produce security guarantees for its northern border. The discussions between Israeli, Lebanese and U.N. military delegations were expected to center on the details of security arrangements in southern Lebanon, including the role of the South Lebanon Army and Israel's proposal for an expansion of the territory patrolled by U.N. troops, which would require Lebanese consent.