* Russia suggests ready to back statement supporting Annan
* Russia, China have twice vetoed resolutions on Syria
* Russian support could mean Moscow's shifting on Assad
By Louis Charbonneau and Michelle Nichols
UNITED NATIONS, March 20 (Reuters) - The sharply divided U.N. Security Council struggled o n T uesday to reach agreement on a statement of support for U.N.-Arab League envoy Kofi Annan's mission to end violence in Syria that has brought the country to the brink of civil war.
The 15-nation panel held two rounds of negotiations on Tuesday on a Western-drafted statement, obtained by Reuters, that would express "full support" for Annan's peace efforts while threatening Damascus with "further measures" if it fails to comply the council's demands within seven days.
The Western push for a "presidential statement" from the council backing Annan's mission comes after Russia and China twice vetoed resolutions condemning Syria's yearlong assault on demonstrators opposed to President Bashar al-Assad that the United Nations says has killed over 8,000 civilians.
After a two-hour closed-door negotiating session, Russian U.N. Ambassador Vitaly Churkin suggested to reporters that Moscow was prepared to back the Western-drafted statement.
"Some need instructions," he said when asked why the council had not approved the statement. "We were ready to go."
But a senior Western diplomat challenged Churkin's remarks, saying it was the Russian envoy who pushed for a delay in the adoption of the statement. "He (Churkin) decided in the end that he wanted to wait until tomorrow morning," the diplomat said.
If no one raises any objections by Wednesday morning, the statement will be automatically adopted without a vote under a process at the United Nations known as a "silence procedure."
Also up for automatic approval on Wednesday morning is a draft of informal remarks to the press that Syria's close ally Russia asked the council to approve. Those remarks would have the council condemn bomb attacks last weekend in the cities of Damascus and Aleppo.
Indian Ambassador Hardeep Singh Puri expressed optimism that the statement would be approved by the council. "Some people want to consult their capitals, but it will work, that's the important thing," Puri told reporters.
Other diplomats said privately that they would not be surprised if Moscow or Beijing asked their delegations to propose further amendments to the draft statement.
If the statement is approved, it would be a further sign that Moscow, which has been Assad's staunchest supporter since he began cracking down on anti-government protesters a year ago, is toughening its position on the Syrian conflict.
Earlier on Tuesday Russian Foreign Minister Sergei Lavrov said that Syria's leadership had made "very many mistakes."
The core of the draft statement is Annan's six-point peace proposal, which calls for a cease-fire, political dialogue between the government and opposition and full access for humanitarian agencies and freedom of movement for journalists.
Assad has banned foreign media from the country.
Western diplomats said privately that their push for a statement backing Annan highlighted their determination to break the impasse on the Security Council that has prevented it from taking any forceful action against Syria since Assad began cracking down on demonstrators a year ago.
Annan, a former U.N. secretary-general, on Friday urged the Security Council to overcome its deadlock and unify in support of his efforts to end the violence.
Unlike resolutions, which are legally binding and need nine votes in favor and no vetoes from the five permanent council members to pass, statements are generally non-binding but require unanimous support from the council.
The latest draft presidential statement is separate from a U.S.-drafted resolution calling on Syria to allow access to humanitarian aid workers in the country.
The last time the council passed a presidential statement on Syria was August 2011, although council members reached a rare unanimous agreement on informal remarks to the press on March 1 to rebuke Damascus for not allowing U.N. humanitarian aid chief Valerie Amos into the country. [ID: nL2E8E1B2A]
Shortly after the council approved those remarks to the press, Amos was allowed to visit Damascus.