The Syrian forces took control of the highway after capturing the villages of al-Baiyarat and Marhatten in Palmyra's western countryside late last week, according to the Iranian news agency FARS.
Right now, the Syrian Army and its allies are stationed about four kilometers from the western walls of Palmyra, the closest the government troops forces have been to the gates of this ancient UNESCO-listed city since July 2015, FARS reported.
Earlier, Syrian and Russian warplanes had launched a volley of airstrikes at militant strongholds close to Palmyra ahead of a major military operation to free the city.
Damascus-led forces carried out missions in al-Sukhneh, al-Sawaneh and Khneifis in the province of Homs, killing an unspecified number of terrorists and destroying the militants' infrastructure.
Palmyra, home to monumental ruins and priceless antiquities, has been on the verge of total destruction since May 2015, when the militants, notorious for reducing cultural sites to rubble, captured the strategically important city.
Although militants did not level Palmyra at the time, they have since destroyed several ancient monuments and are unlikely to stop.
Russia's air campaign kicked off on September 30, when more than fifty Russian aircraft, including Su-24M, Su-25 and Su-34 warplanes, commenced precision airstrikes on Islamic State targets in Syria at the behest of Syrian President Bashar Assad.
