Syrian president Bashar Assad has said his troops did not use chemical weapons in an attack on rebel positions in a Damascus suburb last week where hundreds of people died.
Mr Assad told Russia’s Izvestia daily that the accusations that his troops were responsible were “politically motivated”.
He said in an interview that attacking such an area with chemical weapons would not make sense for the government as there was no clear frontline between regime and rebel forces.
Syria said on Sunday that a UN team could investigate the site, but a senior White House official dismissed the deal as “too late to be credible”.
Mr Assad was quoted as saying: “This is nonsense. First they level the accusations, and only then they start collecting evidence.”
He added: “How can the government use chemical weapons, or any other weapons of mass destruction, in an area where its troops are situated?
“This is not logical. That’s why these accusations are politically motivated, and a recent string of victories of the government forces is the reason for it.”
With France, Britain, Israel and some US congressmen urging swift military action against the Assad regime if the use of chemical agents is confirmed, the UN team’s conclusions could have a dramatic impact on the trajectory of the country’s civil war.
Russia, which has been a staunch ally of Syria, said last week that the accusations against Assad could be a bid to get the Security Council to stand by the opposition, and to undermine efforts to resolve the conflict by convening a peace conference in Geneva.
Meanwhile, members of a UN team that is supposed to investigate the alleged chemical attack have left their hotel in Damascus.
Members wearing body armour were seen leaving in seven SUVs.
It is not clear if the team is headed to the suburb where the alleged attack occurred.
An AP photographer said UN disarmament chief Angela Kane saw them as they left, but did accompany them.