The United States accused Iran in the UN Security Council on Tuesday of illicit arms deliveries to Lebanese guerrillas, endorsing charges by Israel after it seized a ship in the Mediterranean last week.
Britain also raised concerns over what Israeli officials said was the discovery of hundreds of tons of Iranian-supplied arms aboard the ship, intended to be sent via Syria to the Shi'ite Hezbollah group that has fought Israel.
Syria's UN ambassador dismissed the Israeli charges as an "outrageous concoction of lies" and accused the Jewish state of an act of piracy in seizing the Antigua-flagged Francop. Syria and Iran, neither of which currently has a seat on the council, had already denied the allegations.
UN diplomats said no immediate action on the matter was expected from the full council, but that it would likely be referred to a council committee charged with monitoring compliance with a council resolution that bans Iranian arms exports.
Israel formally protested to the United Nations last week over the alleged shipment, after Israeli officials said they had found enough weapons, including rockets, to supply Hezbollah for a month of fighting. They were stored in at least 40 containers headed to Syria from Egypt, the officials said.
The incident was raised by US Deputy Ambassador Alejandro Wolff at a closed-door Security Council meeting discussing developments in Lebanon since a 2006 war between Israel and Hezbollah, diplomats said.
"The November 4 discovery of a concealed arms shipment in commercial shipping containers, clearly manifested from Iran to Syria in violation of Resolution 1747, provides unambiguous evidence of the destabilizing proliferation of arms in the region," a US official said, summarizing the US address.
Britain's deputy ambassador said he too had raised London's "very serious concern" about the affair, but was more guarded about Iranian involvement, saying only there was a "suggestion that Iran has been caught illegally exporting weapons."
Britain was awaiting further information and could not yet confirm details of the Israeli allegations, envoy Philip Parham told reporters.
Syrian Ambassador Bashar al-Ja'afari flatly denied the allegations. "The act perpetrated by the Israelis is an act of piracy on the high seas and the Israelis should be held accountable," he told reporters outside the council chamber.
"I think - and many people think with me, with Syria - that all these are (the) usual Israeli outrageous concoction of lies to justify their act of piracy."
Ja'afari and Lebanese envoy Caroline Ziadeh also criticized the latest report on Lebanon by UN Secretary-General Ban Ki-moon for underplaying Israeli violations of UN resolutions such as surveillance overflights of Lebanon, and focusing more on cross-border shooting by Lebanese guerrillas.
Ban's special coordinator for Lebanon, Michael Williams, denied that the report was unbalanced. "We ask the Israeli government to stop all their violations of Lebanese airspace. I'm not sure how many times I can say this, but if you like I can say it daily," Williams told reporters.
Israel says the overflights are necessary for its security.