Syrian government forces have reached the outskirts of Palmyra, as they seek to retake the ancient city from so-called Islamic State (IS).
The troops and their allies, backed by Russian air airstrikes, are within a few kilometres of the west of the city, state media and activists say.
The jihadists recaptured the Unesco-listed archaeological site in December from government forces.
Parts of the ancient city have been destroyed by the militants.
The pro-government forces seized some hilltops overlooking Palmyra and a strategic area known as the "Palmyra triangle", the official Sana news agency reported.
A media unit run by the allied Lebanese Hezbollah movement later said they had reached the citadel, which sits on a hill overlooking the famous Roman-era ruins.
IS fighters had withdrawn from the area, but suicide bombers might still be there, the UK-based monitoring group Syrian Observatory for Human Rights said.
- Islamic State: The full story
- Blowing ruins to rubble
Interactive See the damage to the ancient ruins
10 January 2017
26 December 2016
IS held the ruins and the nearby city, known locally as Tadmur, for 10 months after seizing it for the first time in May 2015. It blew up temples, burial towers and the Arch of Triumph, believing shrines and statues to be idolatrous.
They also destroyed the Temple of Bel - the great sanctuary of the Palmyrene gods - which had been one of the most important religious buildings of the 1st Century AD in the East.
Ancient city of Palmyra
- Unesco World Heritage site
- Site contains monumental ruins of great city, once one of the most important cultural centres of the ancient world
- Art and architecture, from the 1st and 2nd centuries, combine Greco-Roman techniques with local traditions and Persian influences
- More than 1,000 columns, a Roman aqueduct and a formidable necropolis of more than 500 tombs made up the archaeological site
- More than 150,000 tourists visited Palmyra every year before the Syrian conflict
The militants were then forced out by a Russian-backed government offensive in March 2016, but regained control while pro-government forces where focused on battling for the city of Aleppo late last year.
In January, satellite images revealed that the group destroyed the tetrapylon - a group of four pillared structures which were mainly modern replicas - and part of the Roman Theatre.
Meanwhile, the US said positions held by the their allies of the Syrian Arab Coalition were bombed by Russian and Syrian aircraft near the IS-held town of al-Bab, in northern Syria.
"I believe they thought were held by ISIS, yet they were actually - on the ground - were some of our Syrian Arab coalition forces," Lt Gen Stephen Townsend told reporters, using an acronym for IS.