A senior member of Saudi Arabia's monarchy called on Friday for Syrian rebels to be given anti-tank and anti-aircraft weapons to "level the playing field" in their battle against President Bashar al-Assad.
Insurgents in Syria have seized territory in the north of the country and control suburbs to the east and south of the capital, but Assad's air power and continued army strength have limited their advances 22 months into the conflict.
"I'm not in government so I don't have to be diplomatic. I assume we're sending weapons and if we were not sending weapons it would be terrible mistake on our part," said Prince Turki al-Faisal, a former intelligence chief and brother of Saudi Arabia's foreign minister.
"You have to level the playing field. Most of the weapons the rebels have come from captured Syrian stocks and defectors bringing their weapons," he said at the World Economic Forum in the Swiss mountain resort of Davos.
"What is needed are sophisticated, high-level weapons that can bring down planes, can take out tanks at a distance. This is not getting through."
More than 60,000 people have been killed in the conflict, which started nearly two years ago with mainly peaceful protests but has mushroomed into a civil war that has driven half a million people from the country and displaced many more.
Syria has accused Saudi Arabia, Qatar, Turkey, the United States and France of funding and arming the rebels, something they have all denied. But UN diplomats say that weapons are clearly reaching the rebels via Gulf Arab states and Turkey.
Saudi Arabia has called in the past for the rebels to be armed, but diplomats say that Western countries are reluctant to allow sophisticated weapons into the country, fearing they would fall into the hands of increasingly powerful Islamist forces.
The United States has designated one Islamist group in Syria - the Nusra Front - as a terrorist organisation and expressed concern about the growing Islamist militant strength in Syria.
But the Saudi prince said foreign powers should have enough information on the many rebel brigades to ensure weapons only reached specific groups.
"Levelling the plain militarily should go hand in hand with a diplomatic initiative ... You can select the good guys and give them these means and build their credibility," he said.
"Now they don't have the means, and the extremists have the means and are getting the prestige."