MOSCOW, December 11. /TASS/. More than 4,000 militants of the IS terrorist organization (outlawed in Russia - TASS) have re-grouped to make a new attempt to capture Palmyra, trying to get inside the city to shelter from airstrikes by the Russian air force, the center for reconciliation of the warring parties in Syria said on Sunday.

"More than 4,000 IS militants after having re-grouped undertook another attempt to capture Palmyra," the center said. "Despite big losses in force and equipment, the terrorists are trying to get inside the city, as the Russian air force does not deliver strikes on Palmyra's residential areas."

The military say, IS have relocated forces to Palmyra from Raqqa. Groups, controlled by the U.S. and the international coalition, suspended combat actions there against terrorists. IS's big reserves and armored vehicles were also relocated to Palmyra from Deir ez-Zor.

"The reconnaissance earlier revealed the relocation of up to 5,000 IS militants to Raqqa and Deir ez-Zor from Iraq’s Mosul," the center said. "Now, the Syrian military continue defensive actions in Palmyra."

Earlier on Saturday, press service of the Russian Defense Ministry said the Syrian Armed Forces with the active support from the Russian Aerospace Forces during the past night repelled the Islamic State (outlawed in Russia) militants’ attempts to breakthrough into Palmyra, more than 300 militants were killed.

"During the past night, with the active support from the Russian Aerospace Force, the Syrian governmental forces repelled all terrorist attacks on Palmyra. The attackers used vehicles with suicide bombers, armored vehicles and artillery."

The Russian aircraft delivered 64 strikes on positions, convoys and moving reserves of the militants. "They destroyed 11 tanks and infantry fighting vehicles, 31 vehicles carrying large-caliber automatic guns, more than 300 militants," the ministry said.