Idrees Ali, Warren Strobel, Grant McCool and Andrew Hay
Aug 25th 2016 6:33AM
WASHINGTON, Aug 24 (Reuters) - Four of Iran's Islamic Revolutionary Guard Corps (IRGC) vessels "harassed" a U.S. warship on Tuesday near the Strait of Hormuz, a U.S. defense official said, amid Washington's concerns about Iran's posture in the Gulf and in the Syrian civil war.
The official, speaking on the condition of anonymity, said on Wednesday that two of the Iranian vessels came within 300 yards of the USS Nitze in an incident that was "unsafe and unprofessional."
The vessels harassed the destroyer by "conducting a high speed intercept and closing within a short distance of Nitze, despite repeated warnings," the official said.
IRGC, the Islamic Republic's praetorian guard, is suspicious of U.S. military activity near Iran's borders and appears to be sticking to a familiar posture in the Gulf that predates last year's nuclear accord between Iran and six world powers, including the United States.
The United States and other countries are concerned about Iran's support for Syrian President Bashar al-Assad, its ballistic missile program, and its backing for Shiite militias that have abused civilians in Iraq.
The U.S. defense official said that in Tuesday's incident the USS Nitze tried to communicate with the Iranian vessels 12 times, but received no response. It also fired 10 flares in the direction of two of the Iranian vessels.
"The Iranian high rate of closure... created a dangerous, harassing situation that could have led to further escalation, including additional defensive measures by Nitze," the official said.
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United States and Iran Relations throughout time
United States and Iran Relations throughout time
Return of the hostages from Iran as they step off the plane in Germany. Barry Rosen is second from the bottom waving with no glasses and a beard. He has just announced that he will be going back to Iran to meet with his captors. The hostages were kept over a year in captivity after the US Embassy was stormed during the Iranian Revolution. Relations with Iran and the US have been improving lately. (photo by Tim Chapman)
A Kurdish family having fled northern Iraq, carry all their worldly possessions, reach the border town of Nossod, Iran. Saddam Hussein crushed the Kurdish uprising in northern Iraq in the aftermath of 1991 Gulf War led by the US and allied forces. (Photo by Kaveh Kazemi/Getty Images)
An Iranian woman pets a dove caged in the belly of a replica of the Statue of Liberty at the former US embassy compound November 3, 2001 in Tehran, Iran. Iranian authorities opened the former embassy to the public for the first time since the 1979 Islamic revolution toppled the US-backed Shah which ultimately led to the breaking of relations between Washington and Tehran. (Photo by Keivan/Getty Images)
Reza Pahlavi, son of the late Shah of Iran Mohammad Reza Shah Pahlavi, speaks to New York University students December 4, 2001 in New York City. Pahlavi spoke of the need to root out terrorism and the need for democracy in Iran. (Photo by Mario Tama/Getty Images)
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Deputy Secretary of State Richard Armitage greets people before giving testimony before the U.S. Senate Foreign Relations Committee on Capitol Hill October 28, 2003 in Washington DC. The Committee is hearing testimony on security threats and the U.S. policy toward Iran. (Photo by Mark Wilson/Getty Images)
An Iranian girl rests during a meeting of the conservative group, the Coalition of Builders of Islamic Iran, in Tehran February 16, 2004. The group has taken a tough stance on the country's nuclear prerogatives and a moderate line on US-Iranian relations and the imposition of Islamic social regulations. The main reformist parties are staying away after a conservative-run political vetting body, the Guardians Council, barred some 2,300 people -- most of them reformists -- from even standing in the February 20 polls. (Photo credit: BEHROUZ MEHRI/AFP/Getty Images)
A man holds an effigy of U.S. President George W. Bush during a protest against the U.S.-led occupation of Iraq in Enqelab Square May 19, 2004 in Tehran, Iran. Demonstrators reportedly hurled petrol bombs, firecrackers and stones at the British embassy. (Photo by Majid/Getty Images)
This 18 January file photo shows Secretary of State-designate Condoleezza Rice testifying before the Senate Foreign Relations Committee during her confirmation hearing on Capitol Hill in Washington, DC. US Secretary of State Condoleezza Rice will discuss the war in Iraq and tensions with Iran when she meets Chancellor Gerhard Schroeder on 04 February 2005.(Photo credit: TIM SLOAN/AFP/Getty Images)
U.S. Senator Dick Lugar (R-IN) (C) speaks to the media after addressing the U.N. Security Council at the United Nations February 6, 2006 in New York City. Lugar, along with other Senate Foreign Relations Committee members George Voinovich (R-OH) (R) and Norm Coleman (R-MN), spoke on reform at the U.N., Iran and energy conservation. (Photo by Spencer Platt/Getty Images)
Iranian Foreign Minister Manouchehr Mottaki speaks during a meeting with relatives of the seven Iranian detainees arrested in Iraq by US forces, in Tehran, 18 May 2007. US troops seized seven Iranians in the northern Iraqi city of Arbil on 11 January from what Iran claims was an official consular building. Mottaki said after meeting the families of the detainees that Iran maintains that they were diplomats working for a 'consulate'. (Photo credit: ATTA KENARE/AFP/Getty Images)
Iranian students walk past an anti-US mural on the wall of the former US embassy in Tehran 24 October 2007. Twenty-eight years ago, 19-year-old Iranian chemistry student Massoumeh Ebtekar agreed to join other students in holding more than 60 Americans captive at their embassy in Tehran, an event that was to last 444 days and leave a rupture in US-Iranian relations that has yet to be healed. For Ebtekar, who was elected last year as a member of Tehran city council, there is no contradiction between her prominent role in the embassy siege and her efforts today for greater moderation in the Islamic republic. (Photo credit: ATTA KENARE/AFP/Getty Images)
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USS Nitze had to change course in order to distance itself from the Iranian vessels, the official said, adding that the incident could have led to a diplomatic protest, but the United States does not have diplomatic relations with Iran.
It remains to be seen whether these actions were carried out by rogue Revolutionary Guard commanders or sanctioned by senior officials in Tehran, said Karim Sadjadpour, an Iran expert at the Carnegie Endowment for International Peace.
"For four decades the Revolutionary Guard have been told that America is the greatest threat to the Islamic Revolution," said Sadjadpour. "This institutional culture hasn't changed after the nuclear deal," he added.
In January, 10 U.S. sailors aboard two patrol craft were detained by the IRGC when they inadvertently entered Iranian territorial waters. They were released the next day after being held for about 15 hours.