By Louis Charbonneau
UNITED NATIONS, June 1 (Reuters) - Russia on Saturday blocked a U.N. Security Council declaration of alarm over the bloody siege of the Syrian town of al-Qusair by Syrian troops and Hezbollah guerrillas, Security Council diplomats said.
Britain, president of the 15-nation council, had circulated a draft statement to fellow members voicing "grave concern about the situation in al-Qusair, Syria, and in particular the impact on civilians of the ongoing fighting."
Qusair, near the Syrian-Lebanese border, is usually home to an estimated 30,000 people. Fighting for control of the town has raged for two weeks.
Council statements must be agreed unanimously. Russia blocked the draft text, saying it was "not advisable to speak out as the U.N. Security Council didn't when Qusair was taken by the opposition," a council diplomat said on condition of anonymity.
Another diplomat confirmed the remarks.
Moscow's move to block the statement highlights the deep chasm between Russia and Western nations on how to deal with the two-year-old civil war in Syria that has killed more than 80,000 people. Russian diplomats in New York did not respond immediately to a request for comment.
The draft statement, obtained by Reuters, also urged forces loyal to President Bashar al-Assad and rebels trying to oust him "to do their utmost to avoid civilian casualties and for the Syrian Government to exercise its responsibility to protect civilians."
It appealed to Assad's government "to allow immediate, full and unimpeded access to impartial humanitarian actors, including U.N. agencies, to reach civilians trapped in al-Qusair."
Diplomats said Russia told council members that the best way to deal with Syria was through intensive diplomacy. However, one council diplomat noted that Russia continues to sell weapons to Assad's government.
Moscow in turn has accused Western and Gulf Arab governments of providing money, arms and other forms of support to the rebels. It is an allegation Assad's government has also repeatedly made.
Russia and China have opposed efforts in the Security Council to impose sanctions on Assad's government and vetoed three resolutions condemning it.
Moscow and Washington are trying to organize a peace conference in Geneva this month that would involve the government and rebels. There has been wrangling over who should participate in the conference and no date has been set for it.
Rebels trapped in Qusair have pleaded for military help and medical aid for hundreds of people wounded in the onslaught by government forces. (Editing by Mohammad Zargham)