The Syrian president, Bashar Assad, has said there is no evidence he is responsible for the deadly gas attacks the US government claims left 1,429 people dead, including 426 children.
In an exclusive interview secured by Charlie Rose of PBS, Assad said: "There has been no evidence that I used chemical weapons against my own people."
Assad refused to confirm or deny that he had chemical weapons but said if he did, they were under "centralized control".
The interview will air in its entirety on PBS on Monday night, as president Barack Obama is due to sit down with six television networks for recorded interviews and press his case for a targeted attack on Syria.
On Sunday, the White House asserted on Sunday that "common sense" proved Assad's government was responsible for the chemical attacks in Syria as the US weighs military action.Chief of staff Denis McDonough told NBC's Meet The Press there was "no question in my mind" that Assad had ordered the 21 August attack, outside Damascus.
Obama will set out his case for a strike against Assad in a speech from the White House on Tuesday, amid signs that a majority in the House of Representatives are against intervention.
McDonough told CNN's State of the Union that the evidence available so far showed Assad was to blame. "The material was used in the eastern suburbs of Damascus, that have been controlled by the opposition for some time," he said. "It was delivered by rockets, rockets that we know the Assad regime has and we have no indication that the opposition has."
With video of the consequences of the attack, McDonough said all this added up to "a quite strong common sense test irrespective of the intelligence that suggests the regime carried this out".
McDonough said "nobody doubts the intelligence". "The question for Congress this week is what are the consequences for having done so," he said, on Meet The Press, adding that Congress's decision would be watched closely by Iran and Hezbollah.
"This is an opportunity to be bold with the Iranians." he said. "To make sure they understand that they do not have greater freedom of action, they do not have greater operating space to pursue a nuclear weapon that would destabilize that entire region, threaten our friends and allies and ultimately threaten us."
The United Nations is currently investigating the 21 August attack. Speaking in Paris this weekend, secretary of state John Kerry said said he planned to discuss whether to wait for the UN findings with Obama, adding that the president had not decided on the matter.
McDonough said: "Obviously we are interested in what the UN inspectors have to say." But he added that the UN is "not going to be able to tell us, because their mandate will not allow them to tell us, who is responsible for the attack."
McDonough said: "We are right now focused on Washington … the president ultimately is going to make this decision in consultation with Congress on our timeline as best suits our interests."
On ABC's This Week, McDonough said the US was considering a "targeted, consequential, limited attack against Assad forces and Assad capabilities so that he is deterred from carrying out these actions again.
"Here is what it is not. It is not boots on the ground. It is not an extended air campaign. It is not Iraq, Afghanistan or Libya. This is a very concentrated, limited effort that we can carry out and that can underscore and secure our interests."
Michael McCaul, a Texas Republican and chairman of the House homeland security committee, told Meet The Press: "The problem is I think lobbing a few Tomahawk missiles will not restore our credibility overseas. It's kind of a face-saving measure for the president after he drew the red line.
"Little wars start big wars and we have to remember that. Who are we supporting in this war? We are supporting a rebel faction, a rebel cause, that has now been infiltrated and hijacked by many al-Qaida factions."
McCaul said there was a risk that chemical weapons could end up in the hands of al-Qaida operatives after a US attack. McCaul said, "ironically", that Congress had been debating its next step in Syria on the eve of 9/11.
McCaul also said that while images of victims of the gas attacks were "horrific" and Assad was "a brutal dictator", "I don't want to see those images broadcast in the United States with American kids."
guardian.co.uk © Guardian News and Media 2013
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