Nato said Turkey's membership of the 28-nation bloc is "not in question", despite Turkish president Recep Tayyip Erdogan's friendly meeting with President Putin of Russia.
In a statement, Nato spokeswoman Oana Lungescu described Turkey as a "valued ally, making substantial contributions to Nato's joint efforts".
"Turkey's Nato membership is not in question," she added. "Nato counts on the continued contributions of Turkey and Turkey can count on the solidarity and support of Nato."
The statement comes amid escalating anti-western rhetoric in Turkey, in the wake of last month's failed coup attempt. Erdogan has called for the US to extradite cleric Fethullah Gulen, whom he accuses of being behind the uprising.
In a symbolic reset in international relations between Russia and Turkey, Erdogan met Putin in St Petersburg on Tuesday (9 August), leading to a pledge of increased security cooperation. The two countries had been at loggerheads since November, when Turkey shot down a Russian warplane in northern Syria.
Ahead of the meeting Erdogan criticised the West for its lack of support in the wake of the coup, claiming it cares more about the rights of plotters than Turkish democracy. Russian state TV has amplified Turkish media claims of Western responsibility for the coup.
Nato's second biggest member, Turkey has also recently endorsed the alliance's biggest revamp since the Cold War in response to increased Russian aggression. Recent instability has prompted fears, however, that its commitment to Nato may be weakening.
In the statement, Nato emphasised that its secretary general Jens Stoltenberg had telephoned Erdogan after the coup attempt.
"The Nato secretary general spoke to the Turkish foreign minister on the night of the attempted coup and later with President Erdogan, strongly condemning the attempted coup and reiterating full support for Turkey's democratic institutions.
"He expressed support for the elected government of Turkey and respect for the courage of the Turkish people. He also conveyed his condolences for those who had lost their lives during the coup attempt."