In the wake of the US air strike on a Syrian airbase last week Moscow is sending more ships to Syrian regime controlled waters, a US defence official has said.

Two Steregushchiy-class corvettes, an ocean tug and a fleet oiler left Kaliningrad over the weekend, the unnamed official confirmed to USNI News on Monday.

The Baltic Navy vessels are expected to arrive in the eastern Mediterranean in the next five days and will probably be based in Tartus, which is home to a Russian naval base.

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The surface action group of ships joins the cruise-missile armed Admiral Grigorovich, which began its journey from the Black Sea on Friday.

“The [Grigorovich] will operate in the region in accordance to the changing military situation,” Russia state media reported, adding that it carries cruise missiles, a missile defence system, artillery, anti-aircraft guns, torpedoes, and can dock a helicopter.

The frigate was previously used in the bombardment of rebel-controlled Aleppo last year. The recapture of the city - in large part thanks to Russian firepower - has decisively turned the tide of the war in Russian ally Syrian President Bashar al-Assad’s favour.

In pictures: US missile strike against Syria Show all 7 1 /7 In pictures: US missile strike against Syria In pictures: US missile strike against Syria The guided-missile destroyer USS Porter (DDG 78) launches a tomahawk land attack missile in the Mediterranean Sea AP In pictures: US missile strike against Syria The United States military launched at least 50 tomahawk cruise missiles at al-Shayrat military airfield near Homs, Syria, in response to the Syrian military's alleged use of chemical weapons in an airstrike in a rebel held area in Idlib province EPA In pictures: US missile strike against Syria Shayrat airfield in Syria Getty Images In pictures: US missile strike against Syria US Navy guided-missile destroyer USS Ross (DDG 71) fires a tomahawk land attack missile in Mediterranean Sea Reuters In pictures: US missile strike against Syria US Navy guided-missile destroyer USS Ross (DDG 71) fires a tomahawk land attack missile in Mediterranean Sea Reuters In pictures: US missile strike against Syria President Donald Trump speaks at Mar-a-Lago in Palm Beach, Fla., after the US fired a barrage of cruise missiles into Syria in retaliation for this week's gruesome chemical weapons attack against civilians AP In pictures: US missile strike against Syria Syria's President Bashar al-Assad Reuters

Steregushchiy-class corvettes, some of Russia’s most modern ships, are also capable of firing long range cruise missiles and were used in the Aleppo campaign.

The new fleet joins the six other Russian warships and four support vessels currently stationed in the eastern Mediterranean.

The US maintains a four ships deployment in the same area, including the USS Porter and USS Ross, which were used to launch a barrage of 59 Tomahawk missiles at regime-operated Shayrat airbase near Homs on Friday.

The attack - which marked the first direct action taken by the US against the Syrian government in more than six years of the civil war - killed six soldiers and caused some damage to jets, runways and hangars, but has had little impact on the Assad air force’s capabilities overall.

Russia was among countries that also used the base, but advance US warning to Russian forces ahead of the strike meant that there were no Kremlin casualties.

The retaliatory strike was a “warning shot” from the US over the Syrian government’s alleged chemical weapons attack on the rebel-held village of Khan Sheikhoun last week, which killed at least 80 people. Autopsies carried out by the Turkish Health Ministry showed the victims had been exposed to both sarin and chlorine gas.

Damascus and Moscow have denied the regime attacked the village with chemical weapons, maintaining that the casualties were caused by gases released after an al-Qaeda-affiliated ammunitions depot was hit by conventional munitions in a legitimate government air raid.

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The US attack on a Syrian government target has further complicated the already dazzlingly complex Syrian civil war.

President Donald Trump’s administration had up until last week prioritised defeating Isis as the US’ main focus in the conflict, rather than removing Mr Assad from power.

On Monday, UK Foreign Secretary Boris Johnson said that Russian parties could possibly be subject to economic sanctions over the country’s support for Mr Assad.