Russian President Vladimir Putin had a telephone conversation with his Turkish counterpart Recep Tayyip Erdogan on October 21 to brief him on Syrian leader Bashar al-Assad’s surprise visit to Moscow.

Erdogan has been one of the fiercest critics of the Syrian leader, arguing that the Syrian conflict could be resolved only if Assad leaves power. Turkey has been supporting anti-government forces in Syria since the beginning of the civil war and it allows the US to use its airbases from which American warplanes launch attacks on Islamic State targets in Syria.

Russia also began air strikes in Syria last month, targeting mostly the forces fighting against Assad.

During the phone conversation, Erdogan, reportedly, told Putin that Turkey was concerned the battle for the Syrian city of Aleppo could trigger a new wave of refugees.

Turkey is currently hosting more than 2mn people from Syria, fleeing the civil war in its southern neighbour with which Turkey shares a 900km-long border.

The EU has been discussing with Turkey that refugees use as a springboard to illegally cross into Europe how to stem the flow of refugees. German Chancellor Angela Merkel visited Turkey on October 18 to discuss the issue.

Ankara, however, recently signalled that it may soften its firm stand on Assad. Turkey is ready to accept a six-month transition period in Syria in which Assad would remain a symbolic president, but he will eventually have to step down, according to media.

Meanwhile, the foreign ministers of Turkey and Saudi Arabia, another key player in the conflict, are set to take part in a meeting of Russian foreign minister Sergei Lavrov and US secretary of state John Kerry on Syria scheduled for October 23 in Vienna.

The government’s Syria policy is highly unpopular with the Turkish public. A recent survey by polling company Metropoll found that 56.4% of Turks disapprove the government’s Syria policy, while only 28.9% approve. Critics claim that the government’ ambitious plans to topple Assad have failed and its deep involvement in the Syrian conflict have created unintended results.

A suspected Islamic State militant blew himself up in July in the town of Suruc in south eastern Turkey near the Syrian border, killing more than 30 people. The twin suicide bombings in Ankara on October 10 at a peace rally, believed to be carried out by Islamic State militants, killed more than 100 people, plunging Turkey into deeper political turmoil just ahead of November’s snap elections that are expected to produce a yet another hung parliament.