In an interview with Le Figaro newspaper - his first since the chemical weapons attack on rebel held suburbs of Damascus which killed more than 1,400 people - the Syrian president said it would have made no sense for him to order such an assault.
"Whoever makes accusations should provide proof," he said. "We have challenged the United States and France to provide the slightest proof. (Presidents Barack) Obama and (François) Hollande have been incapable of doing so, even to their own people."
The Syrian leader also issued a warning that France would become an “enemy of Syria” should it take part in military intervention. There would also be repercussions against “French interests” he said.
Mr Assad questioned the “logic” of claims that his forces carried out a chemical gas attack on the outskirts of Damascus on August 21 which the US said killed more than 1,400 people, including over 400 women and children.
“Supposing our army wishes to use weapons of mass destruction. Is it possible that it does so in a zone that it is in, and where soldiers are wounded by these arms that United Nations inspectors have noted in visits to hospitals were they were treated? Where is the logic?” he asked.
He said that the “powder keg” that is the Middle East would “explode” if Western forces struck Syria. “Nobody knows what will happen (after such strikes). Everyone will lose control of the situation when the powderkeg explodes. Chaos and extremism will spread. The risk of a regional war exists,” he warned.
While the French people were not his enemy, the French state would be if it decided to join in the expected US-led attack, he added. “There will be repercussions, negative, of course, on French interests."
The Syrian president's comments, part of a longer interview to be published later on Monday evening, were released by Le Figaro just minutes after French intelligence confirmed the Assad regime was behind a “massive and coordinated attack” on August 21.
The nine-page document - issued by external and military intelligence services and to be presented to lawmakers later on Monday - lays out five points that suggest Assad was behind the attacks. "This poses a major threat to national and global security," the source said.
The intelligence includes satellite imagery showing the attacks coming from government-controlled areas to the east and west of Damascus and targeting rebel-held zones. The source said Assad's forces had since bombed the areas to wipe out evidence.
"Unlike previous attacks that used small amounts of chemicals and were aimed at terrorising people, this attack was tactical and aimed at regaining territory," the source said.
The Syrian leader’s warnings came as Mr Hollande appears increasingly isolated on the international stage as the only Western leader not to put military action a parliamentary vote.
On Saturday, US president Barack Obama put off threatened missile airstrikes, saying he would seek approval from Congress first. The decision came just two days after David Cameron lost a vote in the House of Commons on the principle of taking action to punish Syria for alleged chemical weapons use.
Today the Prime Minister’s official spokesman said the British government has “absolutely no plans to go back to parliament” on the issue. Defence Secretary Phillip Hammond was slightly less categorical, saying: “Circumstances would have to change very significantly before parliament would want to look again at this issue.”
The French parliament is to hold a debate on Wednesday on taking action on Syria but Mr Hollande is under no constitutional obligation to hold a parliamentary vote – which is only required if a military operation lasts more than four months – and has shown no signs of bowing to increasing domestic pressure to do so.
The French president’s aides have made it plain, however, that France will not strike alone if not part of a “coalition”. http://www.telegraph.co.uk/news/worldnews/middleeast/syria/10281519/Bashar-al-Assad-interview-Show-me-the-proof-of-regime-chemical-attack.html