Russia has positioned tanks at an airfield in Syria in what appears to be a continued show of support by the Kremlin for President Bashar Al-Assad, according to US officials.
At least seven Russia T-90 tanks were seen at the airfield near the government stronghold of Latakia, a US official from the State Department told Reuters.
Responding to the reports, State Department spokesman John Kirby told reporters: “It certainly appears as though ... they are continuing to support - and perhaps even with additional assets - the Assad regime.”
Washington has said that the movement on the ground in Syria appears to indicate that Russia intends to create a forward air operating base at the airfield in the port city which has been at the centre of a recent Russian military build-up in Syria.
However, the Syrian Ambassador to Russia has rejected the claims as "a lie" spread by the US.
"We have been cooperating with Russia for 30-40 years in various areas, including the military sphere. Yes, we receive arms, military equipment, all this is done in line with agreements sealed between our countries," Riad Haddad was quoted as saying by the ITAR-TASS news agency.
He went on to say that he wanted to continue consultations between Syrian leaders and opposition representatives ahead of more UN peace talks.
Dmitry Peskov, a spokesman for the Krelmin, declined to comment on the situation at the airfield.
In pictures: Syria conflict
In pictures: Syria conflict
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Syrians carry children amid debris following a air strike by government forces in the northern city of Aleppo
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A Syrian man carries a girl on a street covered with dust following a air strike by government forces in the northern city of Aleppo
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Syrians react as they stand amid debris following a air strike by government forces in the northern city of Aleppo
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A Syrian man carries a girl amid debris following a air strike by government forces in the northern city of Aleppo
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An injured Syrian man walks out from the rubble of a destroyed building following a air strike by government forces in the northern city of Aleppo
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A Syrian woman makes her way through debris following a air strike by government forces in the northern city of Aleppo
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People stand on the rubble of collapsed buildings at a site hit by what activists said was a barrel bomb dropped by forces loyal to Syria's President Bashar al-Assad, in the Al-Fardous neighbourhood of Aleppo
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Syrian residents stand amid the rubble of destroyed buildings
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A Syrian resident grasps a mattress amid rubble in the al-Firdous neighborhood of the northern city of Aleppo
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A bullet-riddled parking sign stands amid debris in a deserted street leading into the old city of Homs
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A general view shows abandoned buildings on a deserted square in the old city of Homs after Syrian government forces regained control of rebel-controlled areas
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A mosque is pictured through shattered glass in the old city of Homs, as rebel fighters withdrew from the city centre in line with a negotiated withdrawal deal with the government after having held out under tight siege for nearly two years
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Buses carrying Free Syrian Army fighters leaving Homs. Exhausted and worn out from a year-long siege, hundreds of Syrian rebels left their last remaining bastions in the heart of the central city of Homs under a cease-fire deal with government forces. The exit of some 1,200 fighters and civilians will mark a de facto end of the rebellion in the battered city, which was one of the first places to rise up against President Bashar Assad's rule, earning it the nickname of "capital of the revolution"
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Syrian government forces hold up a portrait of President Bashar al-Assad (L) while others raise the national flag on top of a pole in the old city of Homs
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Forces loyal to Syria's President Bashar al-Assad run through Aleppo's Bustan al-Qasr crossing after their release by rebels. They were freed as part of a larger deal which saw the last remaining Syrian rebels in central Homs city evacuate their positions and free captives in several locations in northern Syria
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A Syrian woman and two children walk past heavily damaged buildings in the northern city of Aleppo
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A man carries a wounded girl following a reported bombardment with explosive-packed "barrel bombs" by Syrian government forces in the al-Mowasalat neighborhood of the northern Syrian city of Aleppo
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A wounded man sits as he is treated at a makeshift hospital following a reported bombardment with explosive-packed "barrel bombs" by Syrian government forces in the al-Sakhour district of the northern city of Aleppo
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Debris rises in what Free Syrian Army fighters and Islamic rebels said was an operation to strike Al-Sahaba checkpoint, which is considered a gateway to Al-Dayf valley, and remove forces loyal to Syria's President Bashar Al-Assad in Maarat Al-Nouman, Idlib province
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Men try to put out fire at a site hit by what activists said was an air strike by forces loyal to Syria's President Bashar al-Assad in the town of Azaz, north of Aleppo, near the border with Turkey
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Civil Defence members try to put out fire
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Survivors react at a site hit by what activists said was an air strike by forces loyal to Syria's President Bashar al-Assad in the town of Azaz, north of Aleppo, near the border with Turkey
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Residents queue as they wait to receive food aid distributed by the UNRWA at the Palestinian refugee camp of Yarmouk, south of Damascus
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Belongings of Syrian rebels inside a chapel at Crac des Chevaliers, the world's best preserved medieval Crusader castle in Syria. The village was destroyed in fighting between the government and rebel forces while the castle, listed as a UNESCO world heritage site, also has been damaged over the past two years
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Hosen Sabah, a 16-year-old student is comforted by his mother at a hospital in Damascus. Nosen was wounded by a mortar outside his school, while 14 other students were killed and over 80 wounded
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A Free Syrian Army fighter works on a locally made launcher before firing it towards forces loyal to Syria's President Bashar Al-Assad in Mork town
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Syrian policemen and citizens inspecting the site of a car bomb at the entrance of Moadhamiyet al-Sham neighborhood in rural Damascus. According to Syria's Arab News Agency (SANA), a car bomb explosion has gone off in the countryside of Damascus and initial information say there are casualties, where a car rigged with explosions was remotely detonated at the entrance of Moadhamiyet al-Sham neighborhood in rural Damascus during engineering units it was trying to dismantled it
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Opposition fighters carrying a rocket launcher during clashes against government forces in the Sheikh Lutfi area, west of the airport in the northern Syrian city of Aleppo
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A Syrian man helps a woman to make her way through debris following reported air strikes by government forces in the Halak neighbourhood in northeastern Aleppo
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A Syrian man reacts as he carries the body of injured boy following reported air strikes by government forces in the Halak neighbourhood in northeastern Aleppo. According to the Syrian Observatory for Human Rights, at least 33 civilians were killed in the attack
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Syrian rescue workers carry the body of a woman following reported air strikes by government forces in the Halak neighbourhood in northeastern Aleppo
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Syrians gather at the site of reported air strikes by government forces in the Halak neighbourhood in northeastern Aleppo
The reports come after Foreign Minister Sergei Lavrov admitted that "experts" had accompanied military supplies on the ground in Syria.
"There were military supplies, they are ongoing and they will continue. They are inevitably accompanied by Russian specialists, who help to adjust the equipment, to train Syrian personnel how to use these weaponry," Mr Lavrov said.
However, the Kremlin has not confirmed that it has increased its military presence or supplied the Syria government with more arms.
If proven, the latest movements are part of a long-held relationship between Russia and Syria, which has seen the latter provide arms since Soviet times and stand beside Mr Assad in a civil war over which he has been accused of war crimes against his own citizens.
The bloody conflict is believed to have killed more than 140,000 people, and has caused refugees to flee the country and seek security in bordering nations, as well as in Europe.
The US has responded to the expansion of the extremist group Isis in Syria by carrying out airstrikes with a coalition of nations.Reuse content