We remain deeply concerned about Iran‘s contributions to the Assad regime’s brutal campaign against its own people”
Jan PsakiUS State Department spokeswoman
Washington is also concerned about Iran‘s deployment of military personnel in Syria, and its support of Lebanon‘s Hezbollah movement, which had sent fighters to bolster Mr Assad’s forces.
Responding to Mr Ban’s invitation, Syria‘s main political opposition group, the Syrian National Coalition, threatened to withdraw from the Geneva talks.
In a tweet,SNC spokesman Louay Safi wrote: “The Syrian Coalition announces that they will withdraw their attendance in G2 unless Ban Ki-moon retracts Iran‘s invitation.”
In a statement,US State Department spokeswoman Jen Psaki said Washington viewed Mr Ban’s invitation “as conditioned on Iran‘s explicit and public support for the full implementation of the Geneva communique including the establishment of a transitional governing body by mutual consent with full executive authorities.
“This is something Iran has never done publicly and something we have long made clear is required,” Ms Psaki added.
“We also remain deeply concerned about Iran‘s contributions to the Assad regime’s brutal campaign against its own people, which has contributed to the growth of extremism and instability in the region.
“If Iran does not fully and publicly accept the Geneva communiqué, the invitation must be rescinded.”
Syria has been devastated by the conflict which began in March 2011
The SNC had only agreed to attend the talks two days ago.
The coalition’s leader, Ahmad Jarba, said on Saturday that the SNC was going to the talks “without any bargain regarding the principles of the revolution and we will not be cheated by Assad’s regime”.
“The negotiating table for us is a track toward achieving the demands of the revolution – at the top of them, removing the butcher from power,” he added.
US Secretary of State John Kerry welcomed the decision.
“This is a courageous vote in the interests of all the Syrian people who have suffered so horribly under the brutality of the Assad regime and a civil war without end,” he said in a statement.
UK Foreign Secretary William Hague also praised the SNC’s “difficult decision”, adding: “As I have said many times, any mutually agreed settlement means that Assad can play no role in Syria’s future.”
Syrian opposition figures had earlier expressed reluctance to go to Switzerland unless President Assad was excluded from any future transitional government.
Damascus says there cannot be any pre-conditions for the talks.