BEIRUT, Lebanon — Iran allowed Russian warplanes to take off from its territory to bomb targets in Syria on Tuesday, an unprecedented move that underscores the deepening cooperation between two powerhouses heavily invested in the Syrian civil war.
The Iranian deployment increases Russia's foothold in the Middle East and widens Moscow's bombing campaign in Syria, bolstering President Bashar Assad's government ahead of a new round of peace talks the United Nations hopes to convene in coming weeks.
The long-range bombers took off early Tuesday near the Iranian city of Hamedan, 175 miles southwest of the Iranian capital, and struck targets in three provinces in northern and eastern Syria, the Russian Defense Ministry said.
The Russian warplanes then returned to Russia and no Russian forces remained stationed in Iran, the Associated Press reported, citing a U.S. official speaking on condition of anonymity because the official was not authorized to speak to reporters about the matter.
"Russia's use of an Iranian base represents a turning point in Russia's relations in the Middle East. … It sends a powerful message to the United States and regional powers that Russia is here to stay," said Fawaz Gerges, professor of international relations at the London School of Economics.
Russia had talked about the possibility of flying planes out of Iran since late last year, but its decision to do so on Tuesday came as a surprise, U.S. officials said.
Secretary of State John Kerry called Russian Foreign Minister Sergey Lavrov to discuss the operations. Underscoring the U.S. confusion, State Department spokesman Mark Toner told reporters that Washington was "still trying to assess what exactly they're doing."
Col. Christopher Garver, a U.S. military spokesman in Baghdad, told reporters at the Pentagon on Tuesday that the Russians activated a communications link with coalition officials just ahead of the bomber mission.
"The Russians did notify the coalition," he said, adding that they "informed us they were coming through" airspace that could potentially put them in proximity to U.S. and coalition aircraft in Iraq or Syria.
Asked how much advance notice the Russians gave the United States, Garver said: "We did know in time" to maintain safety of flight.
U.S. officials said the setup at the Iranian air base occurred very quickly, perhaps overnight. One military official told the AP that the Russians flew four Tu-22 Backfire bombers to the Iranian air base, along with a Russian cargo plane loaded with the munitions for the bombers, just hours before the bombers flew their missions. The officials spoke on condition of anonymity because they were not authorized to discuss the matter publicly.
Tuesday's action suggests cooperation on the highest levels between Moscow and Tehran, both key allies of the embattled Syrian president, and sends a powerful message to the United States and the Sunni monarchies of the Persian Gulf, which have seen Iran as the archenemy.