Syria's opposition, under pressure to broaden its Islamist-dominated leadership, struggled to overcome deep rifts on Thursday, May 30 and form a united front for a proposed international conference to try to end the Syrian civil war, Reuters reported.

Delegates at inconclusive talks in Istanbul agreed to add 14 named members of a liberal bloc led by veteran figure Michel Kilo to the 60-member assembly of the Syrian National Coalition, the closest body that President Bashar al-Assad's foes have to an overall civilian leadership in the two-year-old uprising.

The coalition also agreed in principle to admit another 14 members of activists' groups from inside Syria and 15 members linked to the Free Syrian Army, an umbrella organization for anti-Assad fighters.

But a neutral mechanism to choose these 29 new members has not been agreed and another battle to name them is shaping up for the next coalition meeting on June 12, members said.

That partial breakthrough, which followed eight days of talks and required the intervention of Turkey and Western and Arab nations, effectively creates a new Saudi-backed bloc in the coalition but leaves Qatar's allies, whose control was threatened by the expansion, with significant influence, coalition insiders said.

International powers fear that unless deep fissures in the opposition ranks are healed, the chances of a successful Geneva peace conference happening soon, sponsored by Russia and the United States, are slight.