Hundreds of Syrian protesters stormed the Turkish border on Friday, with police firing tear gas in an attempt to disperse the crowds.
Demonstrators marched on the Bab Al Hawa border crossing in northern Syria on Friday, demanding that Turkey either open the border or do more to end attacks by government forces and main ally Russia.
Many said they were angered by Turkey’s inaction in the face of a rapid advance, with intensified bombardment in recent days.
The protest comes days after Turkish President Recep Tayyip Erdogan visited Moscow in what was seen by observers as a plea for respite in the Syrian government’s offensive on the last stronghold of opposition to President Bashar Al Assad.
Russian leader Vladimir Putin told reporters that Turkey and Russia had agreed on joint measures aimed at clearing "terrorists" in Syria's Idlib province.
"Together with Turkey's president we have outlined additional joint steps to neutralise the terrorists' nests in Idlib and normalisation of the situation there and in the whole of Syria as a result," Mr Putin said.
Mr Erdogan told the Russian president last week that attacks by the Syrian regime’s forces were causing a humanitarian crisis and threatened Turkey's national security.
However, images of the two leaders eating ice cream together as fighting raged drew anger.
The government renewed its offensive on the area in April, displacing 400,000, according to the United Nations. A ground offensive was launched on August 8, upping the stakes for Ankara, which has established 12 military observation posts in Idlib under a buffer zone agreement reached with Russia.
The region is controlled mainly by Hayat Tahrir Al Sham (HTS), an Al Qaeda affiliate that has vowed to continue the fight against the Assad regime.
Russia and Turkey agreed a deal in September last year to protect the area, but it was never fully put into effect.
Videos and pictures from the Bab Al Hawa crossing, which is close to Reyhanli in southern Tukey, showed hundreds of cars and trucks lining up at the border, crowds pushing their way past border guards and protesters flying Syrian revolutionary flags.
The demonstration came shortly before Russia announced a ceasefire in Idlib, the last rebel stronghold in Syria and home to around three million people, which began at 6am on Saturday.
Earlier this month, Damascus scrapped a similar agreement only three days after it went into effect, accusing rebels and militants of targeting a Russian airbase.