The two made the announcement yesterday in Tehran after a meeting between Iranian Deputy Vice President Mohammad Reza Aref-Yazdi and Syrian Prime Minister Muhammad Naji al-Otari. Following the meeting, al-Otari said, "When such issues are intensified between Syria and Iran, a common tie is formed [between the countries] in developing their relationship."
It wasn't immediately clear what challenges al-Otari was referring to. Neither al-Otari nor Reza Aref-Yazdi mentioned the United States specifically.
Iranian Foreign Minister Kamal Kharrazi appeared to back away from forming a close union with Syria. Speaking in Berlin yesterday, he cast the union more as a promoter of cooperation in the Middle East.
"Iran and Syria have some common interests. This does not mean they are going to establish a united front [against the United States]. But we all have to help and cooperate with each other -- from the European side, from countries in the Middle East -- to solve the problems and crises that the whole Middle East is facing," Kharrazi said.
The announcement was not the first time the two have come together to confront threats from the outside.
Syria -- in spite of its historic ties to Iraq -- supported Iran in the Iran-Iraq War of the 1980s, though that alliance was motivated mostly by personal animosity between Syrian President Hafez al-Assad and Iraqi leader Saddam Hussein.
Syria and Iran also allied to pressure the United States to withdraw from Lebanon in the 1980s and to force Israeli troops to withdraw from that country in 2000.
News of the union comes amid renewed tension with the United States. The United States charges Iran with sponsoring terrorism and trying to build nuclear weapons. Syria, the United States says, also promotes terrorism and actively opposes the U.S.-led coalition in Iraq. Syria and Iran deny the allegations.
The United States has stepped up criticism of Syria following the assassination on 14 February of former Lebanese Prime Minister Rafiq Hariri. Syria, which maintains some 14,000 troops in Lebanon, is suspected of a role in the killing -- though Damascus has denied involvement.
Yesterday, a series of high-ranking U.S. officials used public appearances to sharply criticize both Syria and Iran. Secretary of State Condoleezza Rice, speaking to the Senate Foreign Relations Committee, called Syria a big problem.
"There is no doubt Syria is a big problem. And one of the reasons we have been strong in supporting or in sponsoring [UN] Resolution 1559 [calling on Syria to withdraw its troops from Lebanon] is that we need the international community united against what Syria is doing, and what Syria is using both its own territory for and what it's using the territory of southern Lebanon [for]," Rice said.
She also accused Syria of endangering U.S. forces in Iraq.
U.S. Secretary of Defense Donald Rumsfeld told the Senate Appropriations Committee that Syria, among other things, is harming U.S. efforts in Iraq. "Syria, they're harmful to what we're trying to do," he said. "They're holding Iraqi assets and refuse to release them. They have harbored Ba’athists in their country. They are occupying Lebanon. They are facilitating with Iran, the Hizballah, in Lebanon and Israel. They, during the war, facilitated and permitted the transit of jihadists, busloads of them coming into Iraq to attempt to defeat U.S. forces. And, they've been unhelpful."
The new director of the U.S. Central Intelligence Agency, Porter Goss, used an appearance at the Senate Intelligence Committee to single out Iran. "Even since 9/11, Tehran continues to support terrorist groups in the region such as Hizballah -- it is their state sponsor -- and could encourage increased attacks in Israel and the Palestinian territories to derail progress toward peace there," Goss said. "Iran reportedly is supporting some anticoalition activities in Iraq and seeking to influence the future character of the Iraqi state."
Goss also said Iran continues to hold members of Al-Qaeda.