World leaders arrive in Istanbul for a summit on the ongoing violence in Syria.
They are hoping to pressure the country's president, Bashar al-Assad, to end a crackdown on opposition groups that has left thousands dead.
Among those calling for an end to violence - British Foreign Secretary William Hague
(SOUNDBITE) (English) BRITISH FOREIGN SECRETARY, WILLIAM HAGUE, SAYING:
"The killing continues, it continues to be a completely unacceptable situation."
Western and Arab powers have been criticized for not doing enough to end the violence in Syria, which has entered its second year.
But German foreign minister Guido Westerwelle says momentum is building for a lasting solution.
(SOUNDBITE) (English) GERMAN FOREIGN MINISTER, GUIDO WESTERWELLE, SAYING:
"It's a crucial time. We think the atrocities and the repression of the regime of Assad is no way acceptable so we will increase our measures."
Meanwhile, a couple of dozen supporters of al-Assad gathered outside the summit hall.
They demanded an end to what they called heavy-handed foreign intervention in Syria.
Andrew Raven, Reuters