The main Syrian opposition group has said it will join peace talks that have opened in Geneva. The Saudi-backed High Negotiations Committee (HNC) earlier said it would only join if Syrian government forces ended their air strikes and blockades. UN envoy Staffan de Mistura has already met the Syrian government's delegation in the Swiss city. More than 250,000 people have died and 11 million have fled their homes in almost five years of war in Syria. Forces loyal to President Bashar al-Assad and those opposed to his rule battle each other - as well as jihadist militants from so-called Islamic State (IS). The so-called proximity talks are expected to last for six months, with delegations sitting in separate rooms and UN officials shuttling between them. A senior HNC delegate said the group would send "30, 35 people" to Geneva, the AFP news agency reports. Earlier, Fuad Aliko, a source close to the group, said the delegation would not be acting "as negotiators". Farrah el-Atassi, another activist close to the HNC, told Reuters the team would talk to Mr. de Mistura but also said it would not negotiate directly with the Syrian government. She told the BBC the opposition would focus on humanitarian relief and the release of political prisoners. Separately, US Secretary of State John Kerry on Friday had a phone conversation with the HNC, urging the group to attend the talks. State Department spokesman John Kirby later told reporters that Washington believed it was "important for these talks to continue without preconditions". Mr. de Mistura said he had a "good reason to believe" that the HNC would join the talks on Sunday.