MOSCOW, Aug 3 (Reuters) - Moscow is sending three large landing ships with marines aboard to a Russian naval facility in the Syrian port of Tartus, Russian news agencies quoted a source in the general staff as saying on Friday.
The source said each ship would have up to 120 marines on board and that the vessels, already in the Mediterranean, would arrive in Tartus by the end of this week or early next week.
The source said the ships' mission was to replenish supplies at the small Russian maintenance and repair facility, manned by fewer than 100 personnel, according to analysts.
Russia had earlier said it was preparing to send marines to Syria in case it needed to protect personnel and remove equipment from the naval maintenance facility.
Syria is Moscow's firmest foothold in the Middle East and bought $1 billion worth of weapons from Russia last year, or about 8 percent of total Russian arms exports.
Tartus is the Russian navy's only permanent warm water port outside the former Soviet Union.
The source in the Russian General Staff said the three ships would be joined by three other ships from the Russian Navy's Black Sea and Northern Sea fleets.
The potential loss of Tartus would be a strategic blow to Russia, according to what the Interfax news agency described as a military-diplomatic source.
"Tartus is of extreme military-strategic importance for the Russian Navy, as the backup for the task forces in the Mediterranean. Therefore, its loss would entail deep negative consequences and the actual loss of influence in this key region," Interfax quoted the source as saying.
The Russian Defence Ministry declined comment. The General Staff source said the ships would head back to the Russian port of Novorossiysk after spending several days in Tartus.
Russia has blamed the West for the failure of diplomatic efforts led by U.N.-Arab League envoy Kofi Annan, who resigned on Thursday. Moscow said it regretted his departure.
"He's an honest broker, but there are those who want to take him out of the game to untie hands for the use of force. It's already clear," Russia's Deputy Foreign Minister Gennady Gatilov wrote in his Twitter microblog.
Russia and China have three times blocked Western-backed U.N. Security Council resolutions on Syria that were meant to put more pressure on Syrian President Bashar al-Assad to step down. (Reporting by Gleb Bryanski; Editing by Timothy Heritage and Alistair Lyon)