TASHKENT (Reuters) - The Shanghai Cooperation Organisation (SCO), a China-led security bloc, refused to initiate Iran's accession on Thursday despite a request from Russia which backs Tehran's bid, indicating possible divisions between Beijing and Moscow.

The bloc has served a platform for Moscow and Beijing to project influence in the region. But unlike Russia, China may be reluctant to give it a strong anti-Western flavor.

Iran has long knocked at SCO's door and Russia has argued that with Western sanctions against Tehran lifted, it could finally become a member of the bloc which also includes four ex-Soviet Central Asian republics.

"The Russian position is clear in its support of initiating the SCO admission process (for Iran) without delays, if possible," Bakhtiyor Khakimov, a special SCO envoy of Russian President Vladimir Putin, told reporters as leaders of the bloc's member countries met in Uzbekistan.

"We failed to reach an agreement with our colleagues this time, but the work continues."

Khakimov said there were no objections to the idea "in principle", but there were "technical nuances" related to the timing. He did not name the objecting parties.

A Chinese diplomat who also spoke to reporters in Tashkent on Thursday declined to comment on Iran's bid. But Chinese foreign minister Wang Yi, who visited Uzbekistan last month for a lower-level SCO meeting, said Beijing wanted to focus on the ongoing accession of India and Pakistan before moving on.

(Reporting by Denis Dyomkin and Mukhammadsharif Mamatkulov; Writing by Olzhas Auyezov; Editing by Robin Pomeroy)