Russia's Defence Ministry said on Monday that a Russian SU-30 fighter jet entered Turkish air space “for a few seconds” on Saturday along the border with Syria.
Defence Ministry Spokesman Igor Konashenkov said the breach was caused by "unfavourable weather conditions."
"As you see on the map, the Heymim airbase is located close to the Syrian-Turkish border. The distance is about 30km. Under some of the climatic conditions the planes are approaching the aerodrome from the north. So the following incident was caused by unfavourable weather conditions in this region. Don't look for any conspiratorial reasons here," Konashenkov said.
After Russia’s violation of Turkish air space over the southern province of Hatay which is the neighbour of Syria, Turkey scrambled two F-16 jets on Saturday to patrol the border.
A Russian warplane also violated Turkish air space on Sunday in a second breach over the past three days, a Turkish Foreign Ministry official said. The Turkish military reported a fighter jet, a MiG-29, a type used by both Russia and Syria, harassed two Turkish F-16 jets and locked its radar on to them as they were patrolling the border on Sunday.
The second breach led Ankara to call Moscow’s ambassador on Monday.
Konashenkov said about the second incident, "As regards to the information about the incident with the following of a Turkish jet on Sunday, by an unidentified MiG-29 fighter, it had nothing to do with the Russian air group. There are no planes of this type at the Heymim airbase."
The United States and its NATO allies denounced Russia on Monday for breaching Turkish air space on Saturday. Ankara said if provoked again it would respond.
NATO called on Russia to stop its incursions into Turkish air space, a member country, following an emergency meeting in Brussels on Monday.
The NATO emergency meeting of ambassadors of its 28 member states was held in response to what Secretary-General Jens Stoltenberg called "unacceptable violations of Turkish air space."
NATO members said they “strongly protest” and “condemn” violations of Turkish and NATO territory.
"Allies also note the extreme danger of such irresponsible behaviour. They call on the Russian Federation to cease and desist, and immediately explain these violations," NATO said in a statement after the meeting in Brussels.
The White House also announced that the United States and its allies are seriously concerned by Russian jets violating Turkish air space. It described the Russian incursion as a “provocation” and US Secretary of State John Kerry said the incident caused concern over its potential to escalate the Syrian conflict.
"Had Turkey responded ... it could have resulted in a shootdown, and it is precisely the kind of thing we warned against," Kerry said during a visit to Chile.
White House spokesman Josh Earnest said that Russia presents no indication of changing its strategy of focusing its military efforts in Syria on fighting ISIS.
Russia's actions in Syria will only cause a delay to the political transition the United States has called for in Syria, he added.
Earnest also stated that Russia told Turkey that the Russian jet's violation of Turkish air space was a "mistake."