He added that all foreign forces, including Russians, have to leave Syria when the war is over.

Putin, who spoke at an energy conference in Moscow, emphasized that the Russian military would leave Syria when the war is over if Damascus asks it to.

The US forces currently stationed in Syria, Putin added, violate the UN charter.

Putin’s remarks came days after Syria's Foreign Minister Walid al-Moualem denounced all US, French and Turkish forces operating in his country as "occupying forces" and demanded that they leave immediately while calling on Syrian refugees to come home.

Moualem, who also serves as deputy prime minister, said the foreign forces were on Syrian soil illegally, under the pretext of fighting terrorism, and "will be dealt with accordingly."

"They must withdraw immediately and without any conditions," he told the assembly.

Moualem insisted that the "war on terror is almost over" in Syria, where more than 360,000 people have died since 2011, with millions more uprooted from their homes.

Moualem also announced that despite entering its eighth year of war, the war-ravaged country's goal still stands to eventually return the Israeli-occupied Golan Heights territory as the Syrian army said it is nearing victory in the raging conflict.

“Just as we liberated southern Syria from terrorists, we are determined to liberate fully the occupied Syrian Golan to the lines of June 4, 1967,” the foreign minister said in an address to the UN General Assembly.

President Assad has said that Iran has been invited by Damascus to help regain control of the country, unlike the US-led coalition which he says breaches Syrian sovereignty.