The Pentagon revealed this week that U.S. warplanes in Syria changed their course to avoid a collision with Russian warplanes. The planes took off from Incirlik Air Base in Turkey. Due to Russia inching closer to Turkey, NATO’s chief said the organization has to be ready to protect the country.

“We have taken some actions to ensure the safe separation of aircraft, but we do continue to fly missions over Iraq and Syria in support of this mission to degrade and destroy [the Islamic State in Iraq and Syria],” explained Navy Captain Jeff Davis.

Davis could not provide specific details about the diversion, other than that the planes could not complete their mission in Raqqa, the self-declared capital of the Islamic State (ISIS/ISIL) caliphate.

The U.S. told their pilots “to change their flight path if there is a Russian plane within 20 nautical miles.”

Earlier this week, Lt. Gen. Charles Brown told CBS that Russian aircraft flew extremely close to U.S. aircraft in Syria. Russian planes also violated NATO-member Turkey’s airspace at least twice.

NATO Secretary General Jens Stoltenberg announced it is ready to defend Turkey from Russian aggression.

“All of this sends a clear message to all NATO citizens. NATO will defend you, NATO is on the ground, NATO is ready,” he declared.

Stoltenberg described new plans, which include “a NATO Response Force of up to 40,000, twice the current size.” He also said they plan to construct new headquarters in Hungary and Slovakia.

“We see an escalation of Russian military activity in Syria,” he continued. “And the ministers agreed that Russia’s military escalation in Syria raises serious concerns.”

The Turkish government also pleaded with NATO “to shore up missile defenses in the country aimed at shooting down Syrian rockets.” At the same time, Germany and the U.S. said they planned to “withdraw its Patriot batteries.” Now NATO needs other countries “to plug those gaps.”

German Defense Minister Ursula von der Leyen said they will switch off their batteries next week and bring home their soldiers by Christmas. She insisted the “decision is right.” Reuters noted that her comments suggested “that the Turkish air force id capable of intercepting fighter jets.”

The government summoned the Russian ambassador in the country for a third time on Wednesday. Turkish Foreign Ministry spokesman Tanju Bilgiç said authorities suggested the two countries meet to discuss the numerous airspace violations, which the ruling party found encouraging.

“We find Russia’s request to ‘come together and explain’ positive. Russia is a friend but if the repeated incursions continue, we will perceive it as a threat and not as friendly behavior,” stated Justice and Development Party spokesman Ömer Çelik.

After Russian planes violated the airspace, Turkish President Recep Tayyip Erdoğan warned the Kremlin the continuing violations could eventually mean the nation will “lose Turkey” as an ally.

“An attack on Turkey means an attack on NATO,” he said. “Our positive relationship with Russia is known. But if Russia loses a friend like Turkey, with whom it has been cooperating on many issues, it will lose a lot, and it should know that.”