MONTREUX - The United States on Wednesday led a fierce denunciation of the Syrian regime and vowed it would step up support for the opposition as it seeks to topple President Bashar al-Assad.
The top US diplomat, John Kerry, set the tone when he stressed before 40 nations and international organisations gathered at a landmark peace conference in Switzerland that Assad could play no part in Syria's future leadership.
"There is no way -- no way possible in the imagination -- that the man who has led the brutal response to his own people could regain the legitimacy to govern," Kerry insisted.
"One man and those who have supported him can no longer hold an entire nation and a region hostage," said the US secretary of state, who has led efforts with his Russian counterpart Sergei Lavrov to launch the peace talks and end the three-year war.
At a later press conference in the Swiss city of Montreux, Kerry revealed that Washington and Moscow were also planning to work on other tracks to end the fighting which has left 130,000 people dead.
"There will be parallel efforts being made, even while the talks are going on, to find different pressure points and find a solution," he told reporters from the world's media, refusing to go into detail.
"I will just say to you that lots of different avenues will be pursued, including continued support, augmented support to the opposition."
Washington has provided more than $1.3 billion in humanitarian assistance to the Syrian people, and has been supplying non-lethal materiel such as body armour, communications equipment and night-vision googles to the armed rebels.
But so far it has refused to directly supply weapons and machinery to the opposition forces -- now fighting against both Assad and a wave of Al-Qaeda extremist groups flooding into the chaos.
US military option still on the table
It remained unclear from Kerry's remarks whether the Obama administration was now prepared to review its weapons ban.
And he warned that even though President Barack Obama finally walked away from threatened military strikes against regime targets in September, the US leader "has never taken any option off the table".
As the Syrian sides are set now to start direct negotiations under the aegis of the UN later in the week, Kerry said: "I can tell you this, what you see in the direct talks between the opposition and the Assad regime will not be the full measure of effort being expended in order to try to find a solution here."
Syrian Foreign Minister Walid Muallem earlier dubbed the country's opposition "traitors" and foreign "agents".
He hit back at Kerry's comments, saying only the Syrian people could decide their president, and offered assurances that progress had been made on allowing aid organisations access to stricken populations.
His comments were immediately dismissed by US officials.
"Instead of laying out a positive vision for the future of Syria that is diverse, inclusive and respectful of the rights of all, the Syrian regime chose inflammatory rhetoric," State Department spokeswoman Jen Psaki said in a statement.
US officials said his claim of progress in humanitarian access was "laughable" and if Muallem was serious the regime should immediately open up safe corridors to aid convoys and lift restrictions for advance notice.
Psaki also used her Twitter account @StateDeptspox to hammer away at the Syrian regime, suggesting the Syrian coalition led by Ahmad Jarba better represented the people.
"At #Geneva2 Muallem stays at his del seat. Immovable. SOC has rotated: from Jarba to a Sunni, woman, Druze, Kurd, from all over Syria," Psaki tweeted.
"Which delegation represents Syrian society better?" she added.
The conference marks the first time the regime has sat down at the negotiating table with the Syrian opposition since the uprising erupted in March 2011.
US officials have worked hard behind the scenes for months to unite the divided Syrian opposition and bring them to the talks aimed at charting a path towards a transitional government.
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