Karlov Andrei Gennadyevich, Moscow’s ambassador to Turkey, was shot in an art gallery in Ankara today during an assassination attempt.
The attack is the latest in a string of incidents to rock relations between Recep Tayyip Erdoğan’s and Vladimir Putin’s countries – both of which have vital interests in war-torn Syria.
Russia V Turkey: How tensions have mounted
In November 2015 the Kremlin was left reeling when an attack aircraft was shot down by the Turkish air force.
Russia denied the plane had been over Turkey and called the act a planned provocation by supporters of terrorism.
A string of sanctions from the Kremlin followed as tensions grew between the nations.
Turkish exports of fruit and vegetables to Russia have been banned, visa-free travel has ceased and many Russian travel agencies pulled the plug on tourist packages to Turkey under pressure from the Kremlin.
In September this year, Russia has expressed “grave concern” over Turkey’s brutal military advances in Syria as it continues to back President Bashar al Assad.
This followed accusations Turkey breached Syria’s fragile cease-fire on February 28 by targeting Kurdish forces in northern Syria.
And in retaliation, the Russians cut off Turkey’s primary rebel supply line to Aleppo.
Putin has also bolstered the al-Assad regime, while allowing the Kurdish People’s Protection Units (YPG), the Syrian branch of Turkey’s arch nemesis, the PKK, to take control of territory abutting Turkey, leading many to suggest Moscow is humiliating Turkey.
And experts have said today’s shooting will “further damage Turkey’s international reputation”.
What is more, while Russians arm and back Assad in – Turkish officials say the Syrian president must leave office eventually.
Relations appeared to improve after the military coup in Turkey in July when Russia supported Erdogan after some members of the military attempted to overthrow the Ankara leader’s government.
In August, the leaders met in Saint Petersburg, Russia to improve relations between the two countries.
The two sides have been fighting in Syria for more than five years, while te violence has caused more than 2.5 million refugees from Syria to enter Turkey.
Experts have said the pair are not able to agree over action in Syria.
Military expert Alexander Golts said earlier this year: “I think until now they have no clear decision because it’s clear that their interests are colliding in Syria.”