State Department spokeswoman Victoria Nuland told reporters in Washington that she believed the U.S.-Iran contact occurred on October 12, but did not offer further details.
"We have had direct contact with Iran," Nuland told a briefing. "I'm not going to give you any further details than that, but just to say that we have had direct contact with Iran on this issue."
On October 14, U.S. Representative Ileana Ros-Lehtinen (Republican-Florida), the chairwoman of the House Foreign Affairs Committee, said during a hearing on Iran that the contact took place at the United Nations in New York.
However, Iran's semi-official Mehr news agency quoted Alireza Miryousefi, an official in charge of the media at Iran's UN mission, as saying there had been "no direct contact" between the two countries.
Iran's regime has denied being behind the alleged plot, calling it a fabrication designed to create further tensions between Iran and other Middle Eastern countries.
U.S. President Barack Obama on October 13 said the United States could fully support its allegations that members of the Iranian government had "direct links" to a foiled plot to assassinate the Saudi ambassador to Washington.
In his first public remarks since U.S. officials announced on October 11 that they had disrupted the plot to kill Saudi Ambassador Adel al-Jubeir on U.S. soil, Obama accused Tehran of behaving recklessly and outside international norms.
"This is not just a dangerous escalation," Obama said. "This is part of a pattern of dangerous and reckless behavior by the Iranian government."
One suspect, Gholum Shakuri, is believed to be in Iran, while the other, Manssor Arbabsiar, a 56-year-old naturalized U.S. citizen who also holds an Iranian passport, is in U.S. custody and said to be cooperating with authorities. Officials have tied the plot's planning and financing to Iran's Quds Force, an elite unit of the Islamic Revolutionary Guard Corps.
Speaking at a White House press conference after a meeting with South Korean President Lee Myung-bak, Obama said the allegations against the two men and Tehran's involvement were fully supported by the evidence and that Washington's international allies had been briefed on the details.
Once the evidence was analyzed, he said, "there will not be a dispute" about what happened.
"We also know that [Arbabsiar] had direct links, was paid by and directed by individuals in the Iranian government. Now those facts are there for all to see," Obama said, "and we would not be bringing forward a case unless we knew exactly how to support all the allegations that are contained in the indictment."
U.S. officials have said they will hold Iran "accountable" for its actions and Obama said no options "are off the table." The phrase is seen as diplomatic code for military action.
Obama said Washington will continue "to apply the toughest sanctions and continue to mobilize the international community to make sure that Iran is further and further isolated and pays a price for this kind of behavior."
Meanwhile, Saudi Arabia says it is considering "decisive steps" in its own response. In Vienna, the Saudi foreign minister, Prince Saud al-Faisal, said: "We will not bow to such pressure. We hold [Iran] accountable for any action they take against us."
The statements came after Obama spoke with Saudi King Abdullah on October 12 about the alleged plot.
The White House said Obama and Abdullah agreed that the alleged conspiracy "represents a flagrant violation of fundamental international norms, ethics, and law."
British Foreign Secretary William Hague said on October 13 that it "would appear to constitute a major escalation in Iran's sponsorship of terrorism outside its borders."
He told Parliament that London will work with the United States, the European Union, and Saudi Arabia to agree on an international response.
The U.S. Treasury Department has already imposed sanctions against five people it linked to the alleged assassination plot, including the two men charged over the investigation.
It also imposed sanctions on an Iranian airline, Mahan Air, which it says flew members of the Quds Force and the Iranian-backed Shi'ite militia Hizballah across the Middle East.
On October 13, the Treasury Department's top official for terrorism financing told the Senate Committee on Banking, Housing, and Urban Affairs that the administration was considering additional sanctions on the Central Bank of Iran (CBI) to further isolate the country financially.
The next day, Treasury Undersecretary Cohen told the House Foreign Affairs Committee that the administration was now working with its allies toward potential new sanctions against the CBI.
"We are engaged in an effort to develop the multilateral support that would be, I think, critically important in having an action against the CBI really be effective," he said.
Successive U.S. administrations have been unable to convince their partners, especially Europeans, to adopt multilateral sanctions against the bank.
The bank's core interests include financing Iran's oil and other energy projects, and expanded sanctions could force companies to choose between doing business with the bank or with the United States.
'Iran Remains Determined'
Several senators on the Committee on Banking, Housing, and Urban Affairs urged stronger measures against Tehran.
Committee co-Chairman Richard Shelby (Republican-Alabama) said three decades of "progressively more stringent economic sanctions" had not dimmed the threat Iran poses to the United States and its allies.
"Although sanctions have helped to limit Iran's military capabilities, the events of this week demonstrate, I believe, that Iran remains determined to find new avenues to carry out actions of terrorism," Shelby said.
In an interview on October 13 with Reuters, U.S. Secretary of State Hillary Clinton said the discovery of the alleged plot "will certainly confirm the worst fears by the Saudis, but it will also perhaps strengthen their hand in dealing with the region about the threats posed by the Iranians."
Saudi news agency SPA quoted Abdullatif al-Zayani, the head of the Gulf Cooperation Council (GCC), as saying the purported involvement of Tehran was "severely harmful to the relations between GCC's Arab member states and Iran."
Meanwhile, Iranian official media reported that the Foreign Ministry had summoned the Swiss ambassador, who represents U.S. interests in the country, to "strongly" protest against the U.S. allegations.
Iranian Foreign Minister Ali Akbar Salehi was quoted as accusing the United States of launching a "mischievous scenario," promising that Washington will "apologize" to Iran.
Ali Ahani, the deputy foreign minister in charge of Europe and America affairs, urged Saudi Arabia "not to fall into the trap" of believing U.S. claims, saying that "any disturbance in relations" between countries in the Middle East will only benefit the United States and Israel.
He added, "This pathetic and [conspiratorial] scenario is so clumsy that even American media and political circles are looking at it with doubt."
with agency reports