The Kremlin said Friday that Turkey had provided Russian forces with the target location for an air strike in Syria that accidentally killed three Turkish troops, but Ankara gave a different version of events.
"The situation is obvious, unfortunately. Our military while launching strikes on terrorists followed coordinates that were given to us by our Turkish partners," Kremlin spokesman Dmitry Peskov told journalists.
Along with the three killed, 11 Turkish soldiers were wounded when Thursday's strike -- which was meant to target jihadists -- hit a building where the troops were deployed, according to the Turkish army.
Peskov said the "causes of the incident are clear. There is no debate."
He said there had been a communications failure, adding: "There should not have been Turkish soldiers within the limits of these coordinates. That's why these strikes took place."
But the Turkish military said communications had been in full operation and that the army had provided its Russian counterpart with the location of its units ahead of the incident.
"The Russian armed forces attache in Ankara was invited to the chief of staff headquarters and provided by hand with the coordinates" of the Turkish units at around 20:11 GMT on Wednesday, the military said in a statement on its website.
The coordinates of the Turkish troops were also shared with personnel at the Hmeimim airbase in Syria, Moscow's main outpost for its bombing campaign in support of President Bashar al-Assad, Ankara added.
The Turkish military said it regularly shared information with Russian counterparts on Syria operations as part of an agreement reached by the two countries on January 12 to "prevent units from harming each other".
"Our units hit by the (Russian) plane on February 9 have been located on the same spot for approximately 10 days," the military said.
Russian President Vladimir Putin has expressed his condolences in a telephone conversation with Turkish leader Tayyip Recip Erdogan.
The Kremlin said the leaders agreed after the incident to "enhance military coordination in the course of the operation in Syria against the Islamic State fighters and other extremist organisations".
Turkey and Russia back opposing sides in the Syrian conflict, with Moscow supporting the Assad regime but Ankara pushing for the president's ouster.
The two countries had a ferocious falling-out after a Turkish jet shot down a Russian plane on the Syrian border in November 2015, but have since mended ties and begun cooperation over Syria.
They secured a deal to evacuate Syrians from Aleppo after Russia-backed regime forces retook the city, and have joined forces against the Islamic State group around Al-Bab.