The Syrian National Coalition, the main Western-backed group battling to topple the government of Syria’s Bashar Assad, on Saturday agreed to take part in peace talks in Switzerland next week.
The group’s legal committee approved participation in the talks by a 58-14 vote.
Secretary of State John Kerry praised the decision in a statement Saturday.
"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.
The so-called “Geneva II”' talks, which are actually being held in Montreaux, Switzerland, under the auspices of the United Nations, were brokered by the U.S. and Russia. In the talks, SNC leaders would sit down for the first time with representatives from Assad's government since the country’s bloody civil war broke out in 2011.
The negotiations are scheduled to start Wednesday.
The SNC, which is riven with internal divisions, is Syria's main opposition group in exile. The country's centrist internal opposition group, the National Coordination Body, said Thursday it would not attend.
Kerry, in a press conference reacting to that news, faulted what he called "recent revisionism" about why the peace conference is being held after some three years of civil war in Syria in which more than 100,000 have died and millions have been uprooted.
Kerry said the talks were meant to carry out a 2012 plan calling for a political settlement under which the two sides would together agree on a transitional government.
"For anyone seeking to rewrite this history or to muddy the waters, let me state one more time what Geneva II is about," Kerry said. "It is about establishing a process essential to the formation of a transition ... governing body with full executive powers established by mutual consent."
Reuters contributed to this report.