* Geneva forum holds emergency session on Syria on Friday
* Qatar, Turkey, U.S. seek UN investigation on massacre
* EU wants stronger text but some states prefer consensus
By Stephanie Nebehay
GENEVA, June 1 (Reuters) - The top U.N. human rights body is set to call on Friday for a full U.N. inquiry into a massacre in the Syrian region of Houla after putting initial blame on government bombardment and gunmen loyal to President Bashar al-Assad, diplomats said.
The 47-state forum in Geneva holds an emergency session on Friday - its fourth on Syria in a year - following last week's slaughter of at least 108 people, nearly half of them children.
A draft resolution, circulated late on Thursday at the U.N. Human Rights Council, condemns the "killings confirmed by U.N. observers" in attacks that involved "the wanton killings of civilians by shooting at close range and by severe physical abuse by pro-regime elements and a series of government artillery and tank shellings of a residential neighbourhood".
The Council, which has repeatedly condemned Syria for its crackdown, is likely to adopt the resolution by a wide margin following international outrage at the killings, even if countries including China, Cuba and Russia may vote against it as in the past, Arab and Western diplomats said.
But the text, co-sponsored by the United States, Qatar and Turkey, was not strong enough to win the backing of the European Union, diplomats said.
Negotiations continue on Friday ahead of the special session, scheduled to start at 0900 GMT.
"The general feeling is that the text is weak. That is particularly why the EU is not on board," an Arab diplomat told Reuters, speaking on condition of anonymity.
The massacre, a clear breach of an April 12 ceasefire deal brokered by international mediator Kofi Annan, has prompted leading Western nations to expel Syria's envoys from their capitals.
The office of U.N. High Commissioner for Human Rights Navi Pillay said on Tuesday that most victims were civilians and entire families were shot in their homes. Witnesses told U.N. investigators that most died in summary executions carried out by "shabbiha" militiamen loyal to Assad.
BRINK OF CIVIL WAR
But Syria said its preliminary investigation had shown that anti-government armed groups carried out the massacre with the aim of encouraging foreign military intervention against the government.
Western nations said on Thursday that Syria was on the brink of full-blown sectarian civil war, and urged Russia to end its support for Assad and put pressure on him to stop the bloodshed.
The draft text condemns the killings as violating Security Council resolutions and accuses Syrian forces of "repeated and systematic violations of human rights".
It calls for an existing team of U.N. rights investigators to "conduct a comprehensive, independent and unfettered special inquiry consistent with international standards into the events in El-Houleh (Houla), to publicly identify those responsible for these atrocities and hold them to account".
But the EU is seeking stronger language on accountability - including a possible call for action by the U.N. Security Council - and has proposed amendments, according to diplomats.
"The bottom line is there is still debate over trying to get consensus or a stronger resolution," a Western diplomat said.
"The question is whether to try to keep the Russians on board or sacrifice some of the stronger language. Some would like to create a more pragmatic approach with an eye to New York ultimately," he said, referring to Russia's veto in the U.N. Security Council.
Russia is a staunch ally of the Assad government and one of its main weapons suppliers. A Russian cargo ship that Western officials say was heavily laden with weapons for the government of Syria docked at the Syrian port of Tartus last weekend, a rights group said on Thursday.
The United States and EU have suggested the Security Council should impose an arms embargo and other sanctions on Syria for its 14-month crackdown on anti-government protest in which more than 10,000 people have died. (Reporting by Stephanie Nebehay; Editing by Kevin Liffey)