Iranian Foreign Minister Mohammad Javad Zarif and three deputies will attend international peace talks Friday in Vienna aimed at finding a political solution to the conflict in Syria.

"Based on invitation for the Islamic Republic of Iran to participate in this summit, the foreign minister will be present in Vienna at the head of a high-ranking political delegation for talks on the situation in Syria," Foreign Ministry spokeswoman Marzieh Afkham said, according to Press TV.

"Deputy Foreign Ministers Hossein Amir Abdollahian, Abbas Araqchi and Majid Takht Ravanchi will accompany Zarif on this trip," Afkham added.

It will be the first time that Iran, the main regional ally of Syrian President Bashar al-Assad, has attended talks about ending the four-year-long Syrian civil war, which has killed more than 250,000 people and displaced millions.

Washington had previously opposed Iran's participation, but on Tuesday, U.S. officials said Iran has a "genuine multilateral invitation," indicating that they were able to assuage Saudi Arabia's opposition to Iran attending, noted RT.

Federica Mogherini, the European Union's foreign policy chief who will attend the talks, welcomed Iran, tweeting: "Important to have all relevant regional actors at the table on Friday in Vienna."

Egypt, Iraq, Lebanon, the European Union and France said that they will also attend Friday's meetings, and around a dozen participants are expected in all. It's not clear if invitations were issued to the Syrian government or opposition rebel leaders, though neither side attended the smaller round of negotiations last week, which included the U.S., Russia, Saudi Arabia and Turkey, according to Reuters.

The Syrian National Coalition, a Turkey-based political opposition group supported by Western powers, said that Iran's involvement will undermine the political process. "Iran has only one project - to keep Assad in power... They don't believe in the principle of the talks," the coalition's vice-president, Hisham Marwa, told Reuters.

Iran and Russia have been two of the main countries providing military assistance to Assad as he fights the Islamic State group and U.S.-armed rebels working to overthrow him. Western powers, however, insist that the only way to achieve peace is by forcing Assad to step down. The talks hope to resolve the conflicting opinions.