Turkish authorities reportedly have intelligence suggesting that Russia might be preparing to establish an air base close to Turkey’s border with Syria, a step likely to deepen tensions that flared between the two countries after Turkish warplanes downed a Russian fighter jet in November last year, according to a report.

A Russian delegation led by a lieutenant general flew to the northern Syrian town of Qamishli, right across the border from Nusaybin in southeastern Turkey, on Jan. 16, a news report published in the Hürriyet daily said, quoting unnamed security sources.

Qamishli is being controlled by the Democratic Union Party (PYD), a Syrian Kurdish group that is linked to the Kurdistan Workers’ Party (PKK) terrorist group. Ankara opposes PYD efforts to expand its influence in northern Syria, saying it is a terrorist organization that is no different from the Islamic State in Iraq and the Levant (ISIL).

The Russian delegation conducted extensive inspections in and around the airport in Qamishli, according to the sources. The delegation, which included officials from Russian military intelligence, was accompanied by representatives from the PYD.

Turkish sources suspect that the delegation’s visit is a part of Russian plans to renovate the airport in the town so that it can be turned into a base for warplanes and military cargo planes. This would also entail the installation of radars that would be able to closely monitor Turkish military activities in the area.

After reports that Russia deployed troops to YPG-controlled Qamishli, the Turkish military reinforced the Syrian border with additional tanks and armored vehicles and has started to dig trenches on the border as a security measure.

The Turkish armed forces are now digging trenches on the Turkish side of the border opposite an airport in Qamishli. A large minefield lies between Nusaybin, a Turkish border town in the southeastern province of Mardin, and Qamishli in Syria.

The deployment of Russian troops and military experts to conduct examinations in Kurdish-controlled Qamishli has brought tension between the two countries to a dangerous new level, increasing the prospect of an inadvertent encounter in the area.

These events come after media reports yesterday of an agreement between the US and the YPG for the US to use an airfield in the YPG-controlled part of Hasakah province in northeastern Syria. US military experts are now working to expand the airfield so as to deploy American aerial vehicles, including UAVS, for strikes against ISIL.

The recent developments reveal the complicated nature of geopolitics and the rapidly shifting alignments in Syria’s combustible battlefield, with countless numbers of actors seeking to carve out zones of influence for themselves. Syrian Kurds, who have adopted a non-aligned stance in the Syrian civil war, have cultivated close ties with both the US and Russia to further their own interests, which involve establishing a separate political zone for the Kurdish people.

Speaking in a parliamentary session on Thursday, Deputy Prime Minister Tuğrul Türkeş confirmed Russia’s deployment of a small contingent force in Qamishli. But he played down the nature of the development, saying that a small-scale Russian military presence near the Turkish border is not a significant threat to NATO-member Turkey.

Russia’s foray into Syria’s prolonged war created a new conundrum both for Turkey and the US-led international coalition against the Islamic State in Iraq and the Levant (ISIL).

When a Russian bomber jet violated Turkish airspace after two previous incursions, it prompted Turkish air forces to shoot it down. Subsequently a major dispute broke out between the two nations, triggering a series of sanctions imposed by Moscow on Turkish trade goods.

Following the jet crisis Russia deployed cutting-edge S-400 air defense systems to Syria. This was a move meant to keep Turkish air forces out of Syrian airspace, and one which practically ruled out any Turkish contribution to Western coalition air strikes against ISIL targets in Syria. To avoid another incident, the US urged Turkey to suspend all its flights over Syria.

On Thursday, the US-led coalition carried out new air strikes against ISIL targets in Syria. On the same day, according to Turkish military sources, Russian jets pounded Turkmen positions in western Syria and rural Aleppo, in an intensifying campaign to uproot Western-backed moderate Syrian rebel groups, including Turkmen forces, to the dismay and fury of Turkey and the West.

Russia’s selective targeting of moderate groups has complicated the fight against ISIL, leading to renewed accusations from the West and Turkey, who say Moscow intends to destroy non-ISIL opposition groups rather than fighting the extremist ISIL militants.

Moscow denies charges of watering down its fight against ISIL.

Russian Foreign Ministry Spokesperson Maria Zakharova accused Turkey of sending militants to Syria to join terrorist groups such as the “al-Nusra Front.” She went on to claim that the recent Turkish efforts to build a wall are not intended to boost border security, but rather serve as shelter for terrorists and position from which terrorists can cross the border.

Turkey and Russia frequently engage in tit-for-tat accusations and recriminations over each other’s stance in the Syrian conflict, exacerbating the state of discord among them.