Iran and Russia, the key backers of the embattled Syrian regime, have condemned the United Nations' retraction of an invitation made to Tehran to take part in the Geneva 2 peace talks, a day before the event begins.
UN Secretary-General Ban Ki-moon said on Sunday that the invitation was made after Iranian Foreign Minister Mohammad Javad Zarif said his country was on board with the Geneva I communique, on which the upcoming talks would be based, and that it would play a "constructive and positive role" in the three-year Syria crisis, if it was to participate.
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Iran denied these claims.
"We never asked to take part, we always had the same stance all along, which was clearly expressed and we let our position be known," Marzieh Afkham, Iran's Foreign Ministry spokeswoman, told reporters on Tuesday.
"If the UN changed its mind about the invitation, it's regretful, simply because the secretary-general is under pressure."
Ban rescinded the invitation on Monday after Syria's Western-backed opposition umbrella, the Syrian National Coalition, said it would not attend the talks if Iran was present in Switzerland.
Meanwhile, in Moscow, Russian Foreign Minister Sergey Lavrov described the move as a "mistake, but is not a catastrophe."
"The absence of Iran will not contribute to efforts to ensure the unity of the Muslim world, including in fighting terrorism, which is a threat to all of us and all Muslims as well," Lavrov said.
Syrian President Bashar al-Assad said in an interview with AFP on Monday that the peace talks' main focus will be fighting "terrorism", brushing aside a US-backed transition plan for Syria which does not include his regime.
"That would be the most important result of the conference. Any political result that did not include the fight against terrorism would have no value," said Assad, who is embroiled in an almost three-year-old war with rebels fighting to topple him.
He also added that there was "a significant chance" he will run in the presidential elections on June. "If there is public opinion in favour of my candidacy, I will not hesitate for a second to run for election."