By Seda Sezer
ISTANBUL (Reuters) - Syria's main opposition groups joined together on Sunday to call on the international community to take action to protect Syrian people facing a violent crackdown on pro-democracy protests.
A statement issued in Istanbul on behalf of the newly formed National Council rejected foreign intervention that "compromises Syria's sovereignty" but said the outside world had a humanitarian obligation to protect the Syrian people.
"The Council demands international governments and organizations meet their responsibility to support the Syrian people, protect them and stop the crimes and gross human rights violations being committed by the illegitimate current regime," the statement said.
It also said the Muslim Brotherhood, the Damascus Declaration - the main grouping of established opposition figures - and grassroots activists all had joined the National Council.
While few expect a Libya-style intervention in Syria, the declaration was nonetheless an important show of unity for the opposition, which has been weakened by in-fighting.
"The fact that Islamists, secular figures and activists in the ground are now on one council is a significant," a diplomat in the Syrian capital Damascus said.
"But they still have to demonstrate that they could be politically savvy and able to fill any political vacuum. They need a detailed action plan beyond the generalities of wanting a democratic Syria."
The United Nations says 2,700 people, including 100 children, have been killed in six months of protests against President Bashar al-Assad.
The 46-year old president, who inherited power from his father in 2000, blames the violence on armed gangs backed by foreign forces, while his officials say 700 police and soldiers have been killed, as well as 700 "mutineers."
The authorities have also dismissed the opposition organizing outside Syria as a foreign conspiracy to sow sectarian strife.
The Istanbul declaration was read out by Bourhan Ghalioun, a secular professor of politics living in France. He was flanked by Islamists, including Muslim Brotherhood leader Mohammad Riad al-Shaqfa, Christian and Kurdish politicians and Samir Nashar, a member of the Damascus Declaration.
Among those represented in the Damascus Declaration are former parliamentarian Riad Seif, seen as possibly playing a leadership role if Assad were to fall, and Riad al-Turk, Syria's top dissident.
Turk, 81, but still operating underground, has moral authority over the diverse opposition, having spent 25 years in jail as a political prisoner, including almost 18 in solitary confinement.
France has already publicly supported the National Council, but it has not yet won endorsement from the United States or Syria's powerful neighbor Turkey, which has been enraged by what it describes as brutal killings south of its border.
Assad has relied on Russia and China, which have major oil concessions in Syria and do not want to see Western influence in the Middle East spread, to block western proposals for United Nations Security Council sanctions on the ruling hierarchy.
(Writing by Khaled Yacoub Oweis, Amman newsroom; Editing by Myra MacDonald)