The United States welcomed on Monday the decision of UN Secretary-General Ban Ki-moon to rescind his invitation to Iran to attend an international conference on Syria this week.

“We are hopeful that, in the wake of today’s announcement, all parties can now return to focus on the task at hand, which is bringing an end to the suffering of the Syrian people and beginning a process toward a long overdue political transition,” State Department spokeswoman Jen Psaki said in a statement quoted by The Associated Press (AP).

The statement was released shortly after Ban’s spokesperson confirmed that the UN head had withdrawn the invitation that he issued to Iran on Sunday. The main western-backed Syrian opposition group subsequently dropped its threat to boycott the conference, known as Geneva II.

Secretary of State John Kerry is to attend the conference, which is actually being held in the Swiss town of Montreux, on Wednesday, reported AP.

U.S. officials said earlier Monday that they expected the United Nations would reevaluate the invitation and rescind it unless Iran fully and publicly endorsed the aim of the meeting, which is to begin to prepare a transitional government for Syria that would pave the way for democratic elections there.

That goal was outlined in 2012 in the so-called “Geneva Communiqué,” to which the U.S. and others said all conference participants must embrace. Iran had refused to do so, although the UN said Ban had received assurances from Tehran that it would.

Public statements from Iran after Ban issued the invitation fell “well short” of what was required, the U.S. officials said.

Throughout the civil war in Syria, Iran has provided Assad with military support during his fight against the rebels.

Former Iranian President Mahmoud Ahmadinejad personally sanctioned the dispatch of officers from the Iranian Revolutionary Guards to Syria to fight alongside Assad’s troops.