MOSCOW — Two big powers supporting different factions in the Syrian civil war clashed with each other on Tuesday when Turkish fighter jets shot down a Russian warplane that Turkey said had strayed into its airspace.
The tensions immediately took on Cold War overtones when Russia rejected Turkey’s claim and Ankara responded by asking for an emergency NATO meeting, eliciting more Russian anger and ridicule. After the meeting, the NATO secretary general, Jens Stoltenberg, called for “calm and de-escalation” and said that the allies “stand in solidarity with Turkey.”
It was thought to be the first time a NATO country has shot down a Russian plane in a half-century. And while few expect a military escalation, with neither Russia nor NATO wanting to go to war, the incident highlighted the dangers of Russian and NATO combat aircraft operating in the same theater and has soured chances for a diplomatic breakthrough over Syria.
As President François Hollande of France met with President Obama in Washington to urge a closer and more aggressive alliance with Russia against the Islamic State, Turkey’s decision to fire on a Russian warplane attacking targets in Syria has raised tensions between Moscow and NATO and undercut efforts to persuade Russia to drop its support for President Bashar al-Assad of Syria.
Turkey wants Mr. Assad gone, and has allowed its border with Syria to be an easy crossing point for Syrian rebels, including those the West regards as terrorists or radical Islamists; Russia wants to prop up Mr. Assad and his government. While Moscow says it is attacking the Islamic State, for the most part Russian planes and troops have been attacking the Syrian rebels, some of whom are supported by the United States and the West, who most threaten Mr. Assad’s rule.
Mr. Hollande and Mr. Obama clearly hoped that the bombing of a Russian passenger jet over Egypt, claimed by the Islamic State, would cause Moscow to make defeating the jihadists more of a priority than propping up Mr. Assad. But Tuesday’s events will make that a tougher sell, for President Vladimir V. Putin of Russia wants to be seen as an equal player in the conflict, not beholden to Western policies.
Turkey, especially under the increasingly authoritarian rule of its nationalist president, Recep Tayyip Erdogan, has been fierce in defending its airspace, shooting down Syrian jets that have strayed in the past. Turkey insisted that it issued 10 warnings over a five-minute period to the Russian pilot of the Sukhoi Su-24 to pull away.
But Mr. Putin, clearly angry, responded that the Russian jet had never violated Turkish airspace and was shot down over Syria. Speaking in Sochi, he called the incident a “stab in the back delivered by the accomplices of terrorists,” warning that it would have “serious consequences for Russian-Turkish relations.”
Mr. Putin said that instead of “immediately making the necessary contact with us, the Turkish side turned to their partners in NATO for talks on this incident. It’s as if we shot down the Turkish plane and not they, ours. Do they want to put NATO at the service of Islamic State?”
A United States military spokesman, Col. Steven Warren, confirmed on Tuesday that Turkish pilots had warned the Russian pilot 10 times, but that the Russian jet ignored the warnings. Colonel Warren, speaking from Baghdad to reporters in Washington, also said American officials were analyzing radar track data to determine the precise location of the Russian jet when it was shot down.
At an emergency NATO meeting on Tuesday, Turkish officials played recordings of the warnings Turkish F-16 pilots had issued to the Russian aircraft. The Russian pilots did not reply.
The Turkish account of the episode was described by several diplomats, who asked not to be identified because they were discussing a closed-door session at the alliance’s headquarters in Brussels.
The Russian SU-24 plane was over the Hatay region of Turkey for about 17 seconds when it was struck, according to one diplomat who attended the NATO meeting. But the SU-24 re-entered Syrian airspace after being hit and therefore crashed in Syria, the diplomat said.
Tensions between Russia and Turkey had increased lately over Russian bombing of Turkmen tribesmen in northern Syria, whom Turkey regards as under its protection and who are fighting to oust Mr. Assad. Just this week, Turkey summoned the Russian ambassador in Ankara to demand that Moscow stop targeting Turkmen tribesmen in Syria.
“It was stressed that the Russian side’s actions were not a fight against terror, but they bombed civilian Turkmen villages and this could lead to serious consequences,” the Turkish Foreign Ministry said.
And so it has. The diplomatic spat may have led directly to Moscow continuing to target the Turkmen on Tuesday, and Turkey’s aggressive response.
What may make matters worse is that those same tribesmen say that they shot and killed both Russian pilots as they floated to earth in their parachutes, having apparently ejected safely from their plane, which was brought down by a Turkish F-16 firing air-to-air missiles. And then the tribesmen reportedly destroyed a Russian helicopter with a TOW antitank missile as it tried to rescue the airmen.
The Russian Ministry of Defense confirmed late Tuesday that one fighter pilot had been killed by ground fire and that a marine deployed on the search-and-rescue helicopter died but that the rest of the crew had managed to escape.
NATO countries have been concerned about Mr. Erdogan’s increasingly authoritarian tendencies for some time, and NATO officials acknowledge that Turkey’s agenda in Syria does not always match that of Washington, Britain or France — let alone Russia.
And while he has recently allowed American planes to use Incirlik air base for sorties into Syria, Mr. Erdogan’s own troops have largely turned their fire on the Syrian Kurds, whom Washington regards as its best local ally so far against the Islamic State.
Turkey has been in a struggle for decades with Kurdish separatists in Turkey, labeling them terrorists, and regards the Kurds in Syria and Iraq as sharing the same desire to break away and form a Kurdish state.
In a speech on Tuesday, Mr. Erdogan said there would have been more incidents like Tuesday’s if Turkey had not exercised such restraint.
“The reason why worse incidents have not taken place in the past regarding Syria is the coolheadedness of Turkey,” he said in speech in Ankara. “Nobody should doubt that we made our best efforts to avoid this latest incident. But everyone should respect the right of Turkey to defend its borders.”
While Mr. Hollande is pressing Mr. Obama for tougher action against the Islamic State and plans to travel to Moscow on Thursday to meet Mr. Putin, Washington-Moscow tensions, high over Russia’s annexation of Crimea, were highlighted again on Tuesday when Mr. Obama complained that Russian airstrikes against moderate opposition groups in Syria were bolstering the Assad government instead of trying to destroy the Islamic State.
But the United States and Russia have different interests in Syria, and Mr. Putin has been clear about the need to preserve the existing Syrian government, if not Mr. Assad himself as leader. Mr. Obama, like Mr. Hollande, is committed to the ouster of Mr. Assad and believes that the Syrian strongman is complicit with the Islamic State — from which his government buys considerable amounts of oil — as a means of dividing his own opposition.
In a news conference in Washington with Mr. Hollande, Mr. Obama said: “I do think that this points to an ongoing problem with the Russian operations in the sense that they are operating very close to the Turkish border and they are going after moderate opposition that are supported not only by Turkey but by a number of countries.”
Turkey has the right to defend its territory, Mr. Obama said, but he urged both sides to talk to make sure they figure out what happened and “discourage any kind of escalation.”
Russia’s retaliation so far has been largely symbolic. Foreign Minister Sergey V. Lavrov canceled a Wednesday visit to Turkey, and a large Russian tour operator, Natalie Tours, announced it was suspending sales to Turkey. Russians accounted for 12 percent of all tourists to Turkey last year.
The two countries are also significant trade partners. But “Russia-Turkey relations will drop below zero,” Ivan Konovalov, director of the Center for Strategic Trends Studies, said on the state-run Rossiya 24 cable news channel.
Washington is not interested in getting deeper into Syria with ground troops or having a conflict with Russia. So cautious are the NATO countries about Article 5 of the NATO Treaty, which calls for mutual self-defense, that when Mr. Hollande declared “war” on the Islamic State after the Paris attacks, he invoked the European Union’s toothless Lisbon Treaty and sidestepped NATO. Mr. Hollande was also, French officials have said, eager not to offend Mr. Putin by making Syria a NATO issue.
An earlier version of this article misstated the timing of the downing of an unmanned aerial device. It was last month, not last week.