ANKARA, Turkey, and ABU DHABI, UAE — Moscow deliberately expanded its dispute with the West over Syria when it flew jets over NATO member Turkey's border, observers believe.
At the same time, the situation may cause Turkey to draw more closely with regional partners, in particular Qatar.
Turkey also said an unidentified MiG-29 harassed its jets Oct. 6, prompting the Foreign Ministry to summon the Russian ambassador three times in protest.
The Russian Defense Ministry said that an Su-30 warplane had entered Turkish airspace "for a few seconds" Oct. 3 — "a mistake caused by bad weather" — but NATO on Oct. 6 rejected Moscow's explanation.
The incidents came at a time when Russia was sending more ground troops to Syria and building up its naval presence.
"That was a calculated Russian move," a NATO member state ambassador in Ankara said. "They want to challenge both Turkey and NATO. The message through Turkey is clear: We won't let you decide on Syria's future."
"An attack on Turkey means an attack on NATO," Turkish President Recep Tayyip Erdogan said, citing Article V of the NATO charter.
Turkish Prime Minister Ahmet Davutoglu said on Oct. 7 that Turkey did not want the conflict in Syria turning into a crisis between Russia and NATO nor between Russia and Turkey.
However, he said: "Let me put it bluntly: Turkey's rules of engagement are valid for Syria's, Russia's or another country's warplanes. The Turkish Armed Forces have been issued with open instructions."
Some diplomats think Turkey is bluffing and would avoid any conflict with Russia.
Stoltenberg also condemned as "unacceptable" the recent violations of Turkish airspace by Russian fighters. He criticized the "escalation of Russian military activity in Syria," saying it raises "serious concerns."
Asked about the collective defense of Turkey, Stoltenberg said: "Turkey is a strong ally, our second strongest Army."
Meanwhile, Russia's actions are tightening bonds between Turkey and its gulf cousins.
Turkey and Qatar are becoming particularly close in Syria, where they share similar support for anti-Assad groups that puts them at odds with Russian President Vladimir Putin's support for Assad.
"Both countries are caught in their perfidy in Syria where they either looked the other way on aiding extremists groups including Al-Nusra and ISIL or kept covert relations with these groups in order to avoid direct attention to past mistakes of literally aiding and abetting," said gulf based geopolitical adviser and analyst Theodore Karasik.
In the current situation, Karasik warns that Turkey and Qatar may suffer the most from Russia's actions in Syria.
"The Kremlin knows that its robust backing of the Syrian government augmented by Iranian IRGC [Revolutionary Guard] and Hezbollah may upset some of their other allies who want to see Assad transition out of power and eliminate the threat of extremists," he said.
Esteban Villarejo in Brussels and Aaron Mehta in Washington contributed to this report.