The Russian Foreign Ministry said on Saturday turmoil in Turkey threatened regional stability and called on the Turkish authorities to resolve the situation without violence and within the country's constitutional framework.

It spoke out as forces loyal to the Turkish government fought on Saturday to crush the remnants of a military coup attempt which crumbled after crowds answered President Tayyip Erdogan's call to take to the streets and dozens of rebels abandoned their tanks.

Relations between the Kremlin and Erdogan remain strained over the Syria crisis and the Turkish shooting down of a Russian fighter jet in November despite an agreement last month to resume bilateral cooperation after a period of tension.

"In Moscow we are gravely concerned about events inside the Turkish republic," the Russian Foreign Ministry said in a statement.

"The escalation of the political situation (in Turkey) against the backdrop of existing terrorist threats in this country and of armed conflict in the region pose heightened risks for international and regional stability."

Russian authorities have in the past accused Erdogan of ignoring the smuggling of Islamic State oil from Syria to Turkey and of overseeing what they have called the problematic Islamisation of Turkish society.

Erdogan has rejected the smuggling charges as slander.

Russian trade sanctions on Turkey, imposed over the shooting down of the fighter jet, remain in place despite the Kremlin saying last month that Erdogan had apologised to President Vladimir Putin over the incident.

Prime Minister Dmitry Medvedev said the coup attempt showed something was badly wrong in Turkish society.

"What happened shows that in society and within the army of the Turkish Republic there are powerful deep contradictions which have bubbled to the surface," Medvedev told reporters after a summit in Mongolia.

The Russian Foreign Ministry said it confirmed its readiness to work with Turkey's legitimately-elected leadership, especially when it came to tackling terrorism.

Authorities were working to ensure the safety of Russian citizens in Turkey, traditionally one of the most popular holiday destinations for them, the ministry said. Dmitry Peskov, Putin's spokesman, said officials had been ordered to help Russian nationals return home as soon as possible.

Putin was being kept constantly updated, he added.

The TASS news agency reported that Russian airlines had suspended regular passenger flights to Turkey.

Turkey is one of the largest importers of Russian grain. Russian Agriculture Minister Alexander Tkachev said he hoped the turmoil would not seriously affect exports.-Reuters