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By Margarita Antidze
TBILISI, Nov 14 (Reuters) - Georgian lawmakers failed on Thursday to pass constitutional amendments aimed at holding elections in 2020 under a proportional voting system, triggering protests outside parliament by thousands of opposition and civil activists.
The ruling Georgian Dream Party appeared ready to support changing the system to full proportional voting from next year - one of the demands made at protests that have taken place in the capital Tbilisi since June.
Currently one third of lawmakers in parliament are elected not by party lists, but in single-mandate constituencies.
The switch was scheduled to happen anyway in 2024, but the opposition demanded the change be brought forward, as proportional voting is likely to make it harder for Georgian Dream to maintain its dominance in parliament.
Parliament began discussing the amendments on Wednesday but some ruling party lawmakers, who feared proportional voting would cost them their seats, opposed the changes.
In the ensuing vote on Thursday, 101 lawmakers endorsed the amendments - 12 short of the required majority.
The result prompted a protest rally outside parliament, drawing thousands of people by late afternoon.
"Georgian Dream did not support the democratic development of the country, did not support this most important bill," Giga Makarashvili, an opposition activist, told reporters. "This is a declared war by the Georgian Dream against its own people".
It was not immediately clear whether parliament might reconsider the changes, but strong popular pressure for proportional voting was likely to continue with opposition leaders calling for permanent protests.
Leaders of all main opposition parties met after the vote. They will demand an early parliamentary election by the proportional system and the creation of an interim government, Elene Khoshtaria, an opposition European Georgia party lawmaker, told Reuters after the meeting.
"We will exert pressure on the government by all possible constitutional means," Khoshtaria said.
Opposition leaders said they suspected the abortive vote was orchestrated by Georgian Dream party chief Bidzina Ivanishvili, a wealthy oligarch whom critics suspect in governing the former Soviet republic of 3.7 million people behind the scenes.
"No one believes in this (parliamentary) performance ... This is a very bad decision for the whole society, but first of all for Bidzina Ivanishvili," said Giga Bokeria, an opposition European Georgia party leader.
Ivanishvili issued a statement denying having manipulated the process, saying he was "frustrated by the outcome."
"As leader of the ruling political force, I reaffirm my support for the transition to a proportional electoral system in 2020, and I sincerely regret that it has failed," he said. (Writing by Margarita Antidze; editing by Mark Heinrich and Susan Fenton)