Syrian President Bashar al-Assad denied that he was behind a chemical weapons attack on  the Syrian people and said evidence was not conclusive that there had been such an attack, CBS reported on Sunday on its news program Face the Nation.

"There has been no evidence that I used chemical weapons against my own people," CBS reported Assad said in an interview conducted in Damascus.

The full interview will air on the CBS network and PBS's Charlie Rose show on Monday. Rose said he met with Assad in Damascus. The CBS Face the Nation report was a summary of the interview and did not contain any audio or video of Assad. 

Assad spoke as the Obama administration was pressing its case in the U.S. for congressional authorization of a U.S. strike against Syria in response to the Aug. 21 sarin gas attack that Washington said killed more than 1,400 Syrians, including several hundred children.

Rose, speaking by telephone, said Assad would neither confirm nor deny that Syria had chemical weapons. The United States should produce evidence of his involvement, if it has the evidence, Rose reported Assad said.

Assad warned that if there was a military strike by the United States, there would be retaliation by those aligned with Syria.

US says 'common-sense test' holds Assad responsible

President Barack Obama's top aide on Sunday pressed the case for "targeted, limited consequential action" to degrade the capabilities of Assad to carry out chemical weapons attacks.  

White House Chief of Staff Denis McDonough asserted that a "common-sense test" dictates that the Syrian government is responsible for a chemical weapons attack that Obama says demands a U.S. response. But he said the Obama administration lacks "irrefutable, beyond-a-reasonable-doubt evidence" that lawmakers who will start voting on military action this week are seeking.

"This is not a court of law. And intelligence does not work that way," said McDonough, as part of a five-network public relations blitz Sunday to build support for limited strikes against Assad.

"The common-sense test says he is responsible for this. He should be held to account," McDonough said of the Syrian leader who for two years has resisted calls from inside and outside his country to step down.

McDonough pressed the case for "targeted, limited consequential action to deter and degrade" the capabilities of Assad's regime "to carry out these terrible attacks again.

The U.S., citing intelligence reports, says sarin gas was used in the Aug. 21 attack outside Damascus, and that 1,429 people died, including 426 children.

The number is higher than that, said Khalid Saleh, head of the press office at the anti-Assad Syrian Coalition who was in Washington to lobby lawmakers to back Obama. Some of those involved in the attacks later died in their homes and opposition leaders were weighing releasing a full list of names of the dead.

But the Britain-based Syrian Observatory for Human Rights, which collects information from a network of anti-government activists, says it has so far only been able to confirm 502 dead.

Speaking at a news conference in Paris after meeting key Arab foreign ministers, U.S. Secretary of State John Kerry said they were leaning towards supporting a G20 statement — already signed by 12 countries — that called for a strong international response following an Aug. 21 chemical attack in Syria.

French President Francois Hollande, increasingly under pressure at home and among European partners to seek a UN mandate before any military intervention in Syria, on Saturday suggested he could seek a resolution at the UN Security Council despite previous Russian and Chinese vetoes.

French officials say a draft resolution presented jointly by Britain and France at the end of August was not even read by Russia and China, let alone discussed.

UN inspectors are likely to hand in their report later this week roughly at the same time as the U.S. Congress votes on whether to allow limited strikes on Syria.

"On President Hollande's comments with respect to the UN, the president [Obama], and all of us, are listening carefully to all of our friends," Kerry said.

"No decision has been made by the president."

After the news conference, a U.S. official said Washington was not seeking a vote at the moment.

"We have always supported working through the U.N. but have been clear there is not a path forward there and we are not currently considering proposing another vote," said the official who spoke on condition of anonymity.

'This crosses an international, global red line'

The meeting with Arab ministers, including from Saudi Arabia, Egypt, Qatar and the United Arab Emirates, followed talks in Lithuania with European foreign ministers, who blamed the attack in Syria on Assad but refused to endorse military action.

"All of us agreed - not one dissenter - that Assad's deplorable use of chemical weapons, which we know killed hundreds of innocent people ... this crosses an international, global red line," Kerry said alongside his Qatari counterpart Khaled al-Attiya.

"A number of countries immediately signed on to the G20 agreement that was reached by now 12 countries on the side of the G20 meeting and they will make their own announcements in the next 24 hours about that."

Qatar has strongly backed the Syrian opposition.

"As for Syria and what Qatar is willing to provide, Qatar is currently studying with its friends and the United Nations what it could provide in order to protect the Syrian people," Attiya said without elaborating.

Kerry met his French counterpart Laurent Fabius on Saturday as the two allies look to widen their international coalition against Assad and sway reticent public opinions. Fabius on Sunday repeated that Assad could not be left unpunished.

"If we don't react, that means we're sending, today or tomorrow, a telegram to Assad, to the Iranians, the North Koreans and to all terrorist groups starting with al-Qaeda. We are sending them a telegram saying 'go on, use chemical weapons', and by all means we don't want that" Fabius told France 3 TV.

With files from CBC News