Tensions escalate between Turkey and Russia

Turkish President Tayyip Erdogan has warned Russia not to "play with fire", following reports Turkish businessmen had been detained in Russia,

Russia, meanwhile, has said it is to suspend visa-free travel with Turkey.             

Relations between the former Cold War antagonists are at their lowest in recent memory after Turkey shot down a Russian jet near the Syrian border on Tuesday.

Russia has threatened economic retaliation, a response Erdogan has dismissed as emotional and indecorous.             

The incident has proved a distraction for the West, which is looking to build support for the US-led fight against the so-called Islamic State militant group in Syria.

The nearly five-year-old Syrian civil war has been complicated by Russian air strikes in defence of President Bashar al-Assad.             

Turkey, which has long sought Mr Assad's removal, has extensive trade ties with Russia, which could come under strain.

Mr Erdogan condemned reports that some Turkish businessmen had been detained for visa irregularities while attending a trade fair in Russia.

"It is playing with fire to go as far as mistreating our citizens who have gone to Russia," Mr Erdogan told supporters during a speech in Bayburt, in northeast Turkey.

"We really attach a lot of importance to our relations with Russia ... We don't want these relations to suffer harm in any way."

He said he may speak with Russian President Vladimir Putin at a climate summit in Paris next week.

Mr Putin has so far refused to contact Mr Erdogan because Turkey does not want to apologise for the downing of the jet, a Putin aide said.

Mr Erdogan has said Turkey deserves the apology because its airspace was violated.

Russian Foreign Minister Sergei Lavrov said this afternoon Russia would suspend its visa-free regime with Turkey as of 1 January, which could affect Turkey's tourism industry.

Turkey's seaside resorts are among the most popular holiday destinations for Russians, who make up Turkey's largest number of tourist arrivals after Germany.

An association of Russian defence factories, which includes the producers of Kalashnikov rifles, Armata tanks and Book missile systems, has recommended its members suspend buying materials from Turkey, according to a letter seen by Reuters.

That could damage contracts worth hundreds of millions of euro.             

Russia's agriculture ministry has already increased checks on food and agriculture imports from Turkey, in one of the first public moves to curb trade.                           

Mr Erdogan said that Turkey did not go looking to shoot down a Russian jet but acted after it strayed into Turkish air space.

It was, he said, an "automatic reaction" to standing instructions given to the military. Moscow insists the jet never left Syrian air space.

Lower house speaker Sergei Naryshkin called the incident an "intentional murder" of its soldiers, saying Russia had the right to mount a military response.

The incident has worsened the outlook for the Syrian peace process, dashing recent optimism following the Group of 20 meeting in Turkey where US President Barack Obama held an informal meeting with Mr Putin.             

"It certainly did not help," UN envoy Staffan de Mistura said.

However, Mr Putin did ask France to draw up a map of where groups fighting Islamic State militants operate in Syria in order not to bomb them, France's foreign minister said.