The spokesman for opposition's High Negotiations Committee said the recent developments followed Khan Sheikhoun gas attack are due to delay Astana talks as the White House follows new policy in Syria pushing for ousting Bashar al-Assad.
Dr. Yahya al-Aridi, the key member of Riyadh-based opposition group sees the political equation in Syria has been changed since the U.S. 'made up its mind' forward a political solution without the Assad family after six years of bloodshed and more than half million people killed.
Al-Arid foretasted that the upcoming round of Geneva peace talks in May to carry out new hopes for Syrian people and major change in the negotiations over pressure by the U.S. and International Community.
The HNC is an umbrella body which was created to represent the opposition in the planned Geneva peace talks in 2016.
U.S. President Donald Trump retaliated to the Sarin attack last Friday with a "warning shot" barrage of 59 Tomahawk missiles which struck Shayrat airbase near Homs - the first direct action against Assad's forces taken by the US in more than six years.
On Thursday, al-Assad reiterated to the AFP that his regime had nothing to do with the chemical gas incident that killed more than 103 people, adding that the government gave up its chemical weapons stocks as part of a 2013 agreement.
The international community has condemned the deaths in Idlib province, which most Western intelligence services believe occurred thanks to a deliberate attack carried out by the Syrian government.
On Wednesday, Russia's representative to the United Nations vetoed a Security Council resolution condemning the attack and recommending an immediate international investigation.
The draft text called on the Syrian government to provide flight plans, flight logs and other operational military information from the day of the strike