Lt. Gen. Sergei Rudskoi, operations director of the Russian General Staff, said Wednesday that Russia had conducted joint airstrikes with Turkey against Islamic State targets in Syria. (Yuri Kochetkov/European Pressphoto Agency)

Russia and Turkey conducted their first joint air operations Wednesday in Syria, bombing Islamic State positions in and around the northwestern town of al-Bab, where U.S. jets also struck militant targets this week.

The operations came as Turkish Foreign Minister Mevlut Cavusoglu tweeted that he had a “working breakfast” in Washington with retired Lt. Gen. Michael T. Flynn, President-elect Donald Trump’s designated national security adviser.

The sequence of events reflected Turkey’s ongoing attempts to juggle relations with Moscow and Washington at the dawn of the Trump administration, amid Kremlin efforts to claim an expanding role in Syria’s military and political arenas.

It also brought U.S. and Russian warplanes into their closest potential proximity yet, although a U.S. military spokesman indicated that the American strikes had occurred earlier in the week.

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A U.S. defense official, speaking on the condition of anonymity because he was not authorized to discuss the matter on the record, said the American strikes were not conducted in direct support of Turkish ground troops advancing on al-Bab, but rather as part of attacks against Islamic State targets.

The U.S. military is continuing to discuss the possibility of providing close air support to the Turkish troops. The issue is sensitive because the United States advised Turkey against a rapid move toward al-Bab, about 30 miles south of the Turkish border, and because of U.S. collaboration with Syrian Kurdish forces.

The Syrian Kurds are crucial to U.S. plans to capture the Islamic State’s de facto Syrian capital of Raqqa, about 140 miles southeast of al-Bab. American aircraft and Special Operations forces are assisting and advising ground troops known as the Syrian Democratic Forces, which is composed primarily of Kurds. Turkey says the Syrian Kurds, known as the People’s Protection Units, or YPG, are affiliated with the separatist Kurdistan Workers’ Party, know as the PKK, that both Turkey and the United States consider terrorists.

U.S. officials are concerned that Turkish advances inside Syrian territory will eventually be directed toward the YPG, and will interfere with the upcoming Raqqa offensive. In deference to Turkey’s objections, it has refrained from sending weapons directly to the Kurds. That option, long favored by the Pentagon, is likely to still be on the table when Trump takes over.

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Russia made clear that its air operations are in direct support of Turkey. Lt. Gen. Sergei Rudskoi, operations director of the Russian General Staff, said that “nine attack aircraft of the Russian Aerospace Forces, including four Sukhoi Su-24Ms, four Su-25s and an Su-34 bomber, as well as eight Turkish aircraft” were involved in striking 36 targets.

Turkish aircraft included U.S.-made F-16s and F-4 Phantoms.

Rudskoi called the operation with Turkey, a NATO member, “unprecedented,” and indicated it would continue, according to the Russian news agency Interfax. The two governments signed a military cooperation plan on Jan. 12, he said.

Concern about the PKK, and the Islamic State — which have separately claimed responsibility for several recent terrorist attacks in Turkey — has led Ankara to recalibrate its involvement in Syria’s civil war and its insistence that Syrian President Bashar al-Assad must leave office.

Turkish relations with Russia — Assad’s principal international backer — have warmed considerably in recent months. The two countries, along with Iran, also an Assad ally, are sponsoring a conference, tentatively scheduled for next week in the Kazakhstan capital of Astana, to bring together representatives from Assad’s government and the rebels to negotiate a cease-fire and talks on a political solution to their five-year-old war.

An earlier U.S.-Russian cease-fire effort collapsed amid mutual recriminations last year.

Late last month, Russia’s ambassador to Washington extended an invitation to Trump adviser Flynn to attend the meeting, from which the Obama administration had been purposefully excluded.

Trump has indicated he seeks closer U.S. relations with Russia, and that he considers control of the Syrian government of secondary importance to the fight against the Islamic State. He has criticized President Obama, who has said Assad’s departure from power is crucial to the larger war against the militants, for tensions with the Kremlin.

Trump transition spokesman Sean Spicer said Wednesday that “obviously, what’s going on [in Syria] is of major concern,” and that “if we can find alliances that will help further our national security interests, then we’re going to work with them.” He said, “I don’t know specifically if we’re going to attend the conference or not.”

Cavusoglu, in talks with Flynn and others, brought two primary Turkish concerns. Beyond Syria and the Kurds, Ankara wants a decision on its request for extradition of Fethullah Gulen, a Turkish cleric it has charged with orchestrating an unsuccessful coup attempt in the country last summer. Gulen, who lives in Pennsylvania, holds permanent U.S. residency status.

The Obama Justice Department has said it is still studying the request. Flynn, in an op-ed published the day of the U.S. presidential election, said that the request should be quickly approved.

Missy Ryan contributed to this report.