Lebanon has not yet mustered the support it needs to press ahead with a Security Council vote on a resolution condemning Israeli actions in southern Lebanon, Arab and Western European diplomats said today.

The lack of consensus delayed an anticipated council vote tonight on the Lebanese text, which faces a probable U.S. veto.

As the council debate developed this afternoon, U.S. Ambassador Jeane Kirkpatrick accused some in Lebanon of blackmail, announcing publicly that Lebanese elements -- including a ranking official in the Shiite Moslem militia, Amal -- had threatened to retaliate against Americans there if the United States vetoes the resolution. Kirkpatrick also warned that such threats strike at the very essence of the U.N. Security Council process.

She also refuted a statement by a U.N. spokesman that, as a result of the threats, 33 Americans serving with U.N. peace forces in southern Lebanon had been temporarily withdrawn at U.S. request.

The decision was made by U.N. officials, and there was no such U.S. request, she said. U.S. officials said they had insisted on the correction of the record -- which was confirmed by a U.N. spokesman today -- because "we didn't want to be seen to retreat under a threat."

Kirkpatrick said that three specific threats had been made in the last month against U.S. and British officers serving with the U.N. Truce Supervision Organization in the Beirut area and in southern Lebanon, if the U.S. or Britain were to veto a U.N. resolution condemning Israeli actions.

The first threat came Feb. 8, she said. The second came last Friday, to an American member of the U.N. truce observer team serving in Tyre with the U.N. Interim Force in Lebanon.

The third threat, she said, was made just two days ago by the Amal to a U.N. official in Lebanon.

He warned that countries that use the veto against the Lebanese resolution -- specifically including Britain and the United States -- "will face strong problems."

Lebanese diplomats said they had instructions to proceed to a vote on their resolution without modifications -- whether or not they had the nine votes required under the rules to adopt a substantive resolution.

Without nine positive votes, an American ballot cast against the draft would not constitute a veto.

Among 15 council members, five are expected to abstain, and seven have backed Lebanon, which must win two votes from among Thailand, Peru and Trinidad and Tobago.