* Russia is main diplomatic backer of Assad government
* Security conditions hamper removal of arsenal-Ryabkov
* Says June 30 deadline for elimination process can be met (Adds more quotes and context)
By Alexei Anishchuk
MOSCOW, Feb 3 (Reuters) - Russia stepped up its defence of Damascus on Monday in a dispute with the West over delays in the elimination of Syria's chemical arsenal, saying that President Bashar al-Assad's government was not to blame and that a June deadline could still be met.
In an interview with Reuters, Deputy Foreign Minister Sergei Ryabkov said there was no need to put "political pressure" on Damascus because the delays were the result of a difficult security situation and logistical issues.
The operation to dispose of Syria's stockpile under a deal brokered by Russia and the United States is up to two months behind schedule and a deadline for sending all toxic agents out of Syria this week will be missed, Reuters reported last week.
U.S. officials accused Damascus of dragging its feet and U.S. Secretary of State John Kerry asked Russian Foreign Minister Sergei Lavrov last Friday to put pressure on Assad's government to accelerate the operation.
"We have heard a lot of public statements from representatives of Western countries and international organisations who have cast this issue in a somewhat alarming light," Ryabkov said. "We think there are no grounds for this."
"It was clear from the very beginning that overly tight schedules established last year for the removal of chemicals from Syria would shift," he said, while offering assurances the June 30 deadline for completing the operation can still be met.
"This was linked to the drawn-out process of delivering the materials and equipment needed for this absolutely unprecedented operation," Ryabkov said. "It is also linked, of course, to the very difficult security situation."
Russia has been Assad's most powerful diplomatic supporter during the nearly three-year-old conflict in Syria, using its veto power in the U.N. Security Council to block Western-backed efforts to push him from power or impose sanctions.
Despite sharp differences, Russia and the United States have joined forces to initiate peace talks and to press Syria to eliminate its chemical arsenal after a poison gas attack that killed hundreds near Damascus in August.
Assad's swift agreement to the plan, first proposed by Russia, helped avert potential U.S. air strikes. But the delays have caused many in the West to suspect he is stalling and ask whether Russia can and will lean on him to speed it up.
Ryabkov dismissed such suspicions, saying: "Damascus is approaching this process in an extremely responsible way."
"I see complete commitment on the part of the country's leadership ... to fulfilling these agreements," Ryabkov said. "The pace is another thing, and after all we are only at the very beginning of February, and there is certainly enough time to do everything that is planned."
Russia hopes shipments out of Syria will continue soon, he said, adding that Damascus was concerned about security and suggesting Moscow thought its requests for more equipment legitimate. A U.S. official last week dismissed the requests as a stalling tactic.
"These are reasonable, serious considerations, so it would probably be wrong to apply political pressure on the Syrians, heating up the situation and politicising this whole process," said Ryabkov.
Russia is helping escort shipments out and has supplied 75 trucks and armoured vehicles to transport toxic agents to the port of Latakia for removal for destruction abroad, but Ryabkov said Russian personnel were not involved in the convoys.
"One of the reasons why the volume of toxic materials that has been sent out is not as substantial as many would have hoped is that the security situation does not allow the Syrians to intensify this process," he said.
He gave no specific details but said Russia and all those who were in contact with groups that influence forces opposing the government must work with them to avoid attacks or other efforts to undermine the process. (Reporting by Alexei Anishchuk; Editing by Steve Gutterman, Kevin Liffey and Gareth Jones)