Clinton's arrival on Saturday comes a day after Washington announced its sanction on the government of Syrian President Bashar al-Assad and his allies.

US officials say the secretary of state is to meet with Turkish President Abdullah Gul, Prime Minister Recep Tayyip Erdogan and Foreign Minister Ahmet Davutoglu, to discuss "how to support the opposition".

Turkey has also imposed sanctions on Syria in a move aimed at increasing pressure on Assad and paving the way for his ouster.

Turkey's sanctions include the freezing of the Syrian government's assets as well as travel bans on senior Syrian officials.

The US and Turkey have both been explicitly supporting the insurgents carrying out deadly attacks inside Syria.

Damascus has accused several regional countries including Turkey, Saudi Arabia and Qatar of funding and supplying weapons to armed gangs in the country.

On Tuesday, more than 100 Turkish troops armed with thermal rockets and sophisticated weaponry briefly entered the town of Cerablos in Syria's Kurdish region of Kobani.

Last week, the Turkish Army also staged tank exercises in the Nusaybin district of Mardin province, just two kilometers away from the Syrian border.

Meanwhile, Britain has also publically expressed its support for a regime change in Syria by offering the opposition USD 7.8 million in financial aid, and providing groups seeking the ouster of Assad with medical supplies, body armor, and communication equipment.

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  • Recent reports suggest the Turkish government had used ambulances to smuggle arms and ammunitions into Syria to be used by insurgents in the country.

Syria has been experiencing unrest since March 2011. Damascus says outlaws, saboteurs, and armed terrorists are the driving factor behind the unrest and deadly violence while the opposition accuses the security forces of being behind the killings.