Iran on Friday became the second OPEC country to call for an oil embargo against Israel's allies.

Iranian supreme leader Ayatollah Ali Khamenei said Muslim oil-producing states should halt supplies to countries supporting Israel.

"I suggest, only for one month, as a symbolic gesture, that Arab and Islamic countries switch off oil to all countries who have close relations with Israel," Khamenei said in a Friday prayer sermon at Tehran University. 

Khamenei did not elaborate on which countries should be targeted or whether Iran would take such action unilaterally.

During a visit to Moscow, Iranian Foreign Minister Kamal Kharrazi suggested his government would support Khamenei's suggestions.

"If other Islamic countries join in this call, it will be a very strong instrument against America and Israel," Kharrazi said.

Three days ago, Iraqi Foreign Minister Naji Sabri proposed that Arab countries use oil to pressure the United States into forcing Israel to end its military offensive in the West Bank.

Iraq also belongs to the Organization of Petroleum Exporting Countries, which pumps about a third of the world's crude. The last Middle Eastern oil embargo against the West was in 1973 because of an Arab-Israeli war.

OPEC secretary-general Ali Rodriguez told Dow Jones Newswires an oil embargo would counter the organization's goal of promoting a secure oil supply and stable prices.

Rodriguez also said through a spokesman that OPEC has not received any member proposal for an oil embargo against nations sympathetic to Israel.

World markets initially were alarmed by Iraq's earlier boycott call, as crude futures surged to six-month highs Tuesday, pushing prices at U.S. pumps higher.

Those world prices stabilized Thursday, however.

Oil analysts said an embargo would be ineffective. Saudi Arabia and Kuwait would have to participate for it to be successful and both have signaled they would not join such a boycott.

Also, non-OPEC producers such as Russia, Mexico and Norway likely would pump more oil to cover any supply shortage, analysts said.

OPEC and other major oil exporters pledged in November 2000 not to use oil as a political weapon, although Iraq did not attend that meeting.