British Foreign Secretary William Hague on Tuesday called upon all sides involved in Syria's bloody civil war to "seize the chance" of peace ahead of crucial talks in Switzerland.
Hague, international diplomats and representatives of Syria's warring sides arrived on Tuesday for the conference.
"Both sides should seize chance to end the war," Hague wrote on Twitter. "100,000+ Syrians have died in 18 months since Geneva I".
US Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov are already in Switzerland, where the peace talks begin Wednesday in the town of Montreux on Lake Geneva.
The Syrian opposition will be at the talks after the United Nations withdrew an invitation to Iran, a key ally of President Bashar al-Assad.
"Opposition has been tested and has come," Hague added. "Now regime must be tested on willingness to seek a political solution".