Iran will not be at the table during the United Nations-moderated discussions regarding the Syrian crisis Wednesday, the BBC reported.

After the U.S. and Syria's opposition group, the National Coalition, expressed anger over the U.N. extending an invitation to the country, Iran’s invite was rescinded and a U.N. spokesman criticized the country's failure to back the plan to form a transitional government in Syria. Iran, on Monday, had issued statements rejecting conditions on its attendance at the conference.

Martin Nesirky, a spokesperson for U.N. Secretary-General Ban Ki-Moon, said Iran, an ally of the Syrian regime, "has made a disappointing public statement." The rebuke came after the invitation was extended to Iran following its previous assurances that the country would support a transitional government for Syria. 

The National Coalition, which is the chief opposition group in Syria, had threatened to boycott the meeting if Iran were present at the talks between Bashar Assad's regime and opposition forces, which are set to begin Wednesday. 

Regarding Iran’s most recent statements, which rejected a conditional invitation to the talks, Nesirky added via the BBC: "Given that it has chosen to remain outside that basic understanding, he (Ban) has decided that the one-day Montreux gathering will proceed without Iran's participation."

Syria’s civil war has reportedly resulted in the death of more than 100,000 people and displaced millions more. On Wednesday, the Syrian government and the National Coalition are both slated to send delegates to meet at the conference in the Swiss town of Montreux.

Rescinding the invitation was "the right thing to do," Monzer Akbik, the National Coalition's chief of staff, told the BBC. It’s not known if Iran will join future talks when they move to Geneva.

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