Any foreign intervention in Syria would be an act of aggression unless it is approved by Damascus, a Syrian government minister said on Thursday, after the United States said it was prepared to strike against Islamic State militants in the country.
Syria has repeatedly warned that any action on its soil needs its approval and has said it is willing to work with any country to tackle Islamic State fighters who have captured large areas of Syria and neighbouring Iraq.
"Any action of any type without the approval of Syrian government is an aggression against Syria," Ali Haidar, minister of national reconciliation affairs, told reporters in Damascus.
"There must be cooperation with Syria and coordination with Syria and there must be a Syrian approval of any action whether it is military or not."
Foreign countries could use Islamic State simply as a pretext for attacking Syria, Haidar told reporters ahead of a meeting with new international peace mediator Staffan de Mistura.
Washington and its Western allies have supported the insurgency against Syrian President Bashar al-Assad and have ruled out cooperating with him to fight Islamic State, which seeks to create a cross-border caliphate.
Instead the United States wants to bolster moderate Syrian rebels fighting Assad and has asked Congress to authorise $500 million to train and arm them, and has said it is willing to carrying out air strikes against Islamic State targets in the country.
Speaking in Damascus after meeting with Assad and other senior Syrian officials, U.N.-appointed mediator Mistura said it was important for the international community to tackle radical militant groups in Syria.
"The terrorist threat has become an international concern shared by everyone," he told a news conference, adding that the international community was getting closer to taking action.
He said he had a "very long and useful meeting" with Assad, but declined to give details, saying only that the United Nations would work with Syria to help tackle the violence, provide humanitarian aid and work on a solution to the crisis.
"Syrians, wherever they are, and the government should be helped by the United Nations and the international community to find a Syrian-owned all-inclusive, positive, political process," he said.
Syria has said it is willing to work with Mistura and has called on him to be fair and respect the wishes of the Syrian people.
Also on Thursday, Syria's Western-backed National Coalition opposition said it was ready to work with the United States against Islamic State militants after President Obama authorized US air strikes for the first time in Syria.
Saying it had "long called for this action" and had repeatedly warned about Islamic State, the coalition called again for its military wing, the Free Syrian Army, to receive support to form a "reliable and well-equipped force."
"We urge the US Congress to approve the president's policy as soon as possible, and to allow the training and equipping of Free Syrian Army," coalition president Hadi al-Bahra said in a written statement.
The coalition, which is based in Turkey, has received support and recognition from the Western powers and Gulf Arab states who are among Syrian President Bashar al-Assad's most vocal opponents, but has struggled to win support on the ground.
Instead, hardline Islamist groups, including the Nusra Front, al Qaeda's affiliate in Syria, have come to dominate the battlefield.
The coalition also said it was "equally important" to realize that Assad's government was "the root cause of the violence, brutality, and sense of impunity prevailing in Syria", and urged action against it as well.
"The Syrian Coalition ... stands ready and willing to partner with the international community not only to defeat ISIS but also rid the Syrian people of the tyranny of the Assad regime," it said, using another name for Islamic State.
"Combating ISIS alone cannot bring about a stable and extremist free region," it said.
REUTERS