Turkish, U.S. and Ukrainian officials discussed the latest situation in the ongoing war with Russia in a trilateral format in Istanbul on Sunday.

Presidential Spokesperson Ibrahim Kalın, U.S. National Security Adviser Jake Sullivan and Head of the Office of the President of Ukraine Andriy Yermak met at the Mabeyn Mansion.

"Discussed the current situation at the front lines and the coordination of measures to respond to Russia's latest aggressive actions," Yermak said.

"Emphasized the need for Ukraine to obtain reliable international security guarantees before our country becomes a NATO member," he added on Twitter.

He said separately that he discussed the current situation at the front lines with Kalın, some specific issues of Ukrainian-Turkish defense cooperation, and support of initiatives within international organizations.

Kalın for his part, underlined that the war has to be ended on the basis of international law and the sovereignty and territorial integrity of Ukraine while dialogue must be reinitiated.

Reiterating that Türkiye rejects the illegal annexation of four Ukrainian provinces by Russia, Kalın added that despite the difficult conditions, Ankara is continuing its efforts to bring the two sides together.

Most recently, Türkiye enabled a prisoner swap between the warring countries.

One of the most important outcomes of Turkish mediation was when Türkiye, the United Nations, Russia and Ukraine signed a deal in Istanbul to reopen certain Ukrainian ports to release grain that had been stuck for months because of the ongoing Russia-Ukraine war – a development that has been crucial in responding to a growing global food crisis.

Türkiye is one of the most active countries working to ensure a permanent cease-fire between Ukraine and Russia. Its delicately balanced act of assuming a role as a mediator by keeping communication channels with both warring sides open provides a glimmer of hope in diplomatic efforts to find a solution and achieve peace in the Ukraine crisis.

With its unique position of having friendly relations with both Russia and Ukraine, Türkiye has won widespread praise for its push to end the war.

Since the beginning of the conflict, Ankara has offered to mediate between the two sides and host peace talks, underlining its support for Ukraine’s territorial integrity and sovereignty. While Ankara has opposed international sanctions designed to isolate Moscow, it also closed its straits to prevent some Russian vessels from crossing through them.

In a breakthrough, Russian and Ukrainian delegations met for peace talks in Istanbul on March 29 as the war entered its second month, with casualties piling up on both sides.

Türkiye also hosted the foreign ministers of Russia and Ukraine in Antalya in March.

Kalın and Sullivan also discussed bilateral ties, economic relations, defense cooperation as well as regional issues including the South Caucasus and the Aegean.

With the implementation of the Strategic Mechanism, the expectation of increasing cooperation areas on the basis of common interests was expressed.

Last October, meeting in Rome, President Recep Tayyip Erdoğan and his U.S. counterpart Joe Biden agreed to establish a strategic mechanism that promotes high-level dialogue and addresses issues on which Türkiye and the U.S. do not fully agree, along with issues they are working on.

During a visit this April to the Turkish capital Ankara by Victoria Nuland, the U.S. undersecretary of state for political affairs, the Türkiye-U.S. strategic mechanism was launched.

Turkish-American relations have been strained in recent years due to U.S. cooperation with the PKK terrorist group's Syrian branch, the YPG, its failure to extradite the wanted ringleader of the Gülenist Terror Group (FETÖ), disagreements over Türkiye's purchase of Russia's S-400 air defense system and Washington's sanctions on Türkiye.

It was also underlined that completing the F-16 process would serve both countries’ strategic interests.

A delegation of members of Türkiye’s ruling party departed for Washington last Tuesday to hold talks on the potential sale of the F-16 fighter jets, as the prolonged process continues to top the agenda in bilateral contacts.

Türkiye has been seeking to modernize its air fleet and sought to buy 40 F-16 jets and nearly 80 modernization kits from the United States.

The U.S. House of Representatives in July approved legislation that would bar the sale to Ankara unless the Biden administration certifies that doing so is essential to U.S. national security. It also includes a description of concrete steps taken to ensure they are not used for "unauthorized overflights" of Greece.

Ankara has been voicing its firm opposition to any conditions on the sale of the jets.

While it was emphasized that Türkiye would not hesitate to protect its rights and interests in the Aegean and Mediterranean issues, it was stated that the aggressive actions of Greece against international law were unacceptable.

Tension has risen in recent months between Greece and Turkey, fellow members of the NATO defense alliance, which have long feuded over maritime borders and energy exploration rights in the Aegean and the Eastern Mediterranean seas.

Türkiye last week lodged a protest with the U.S. and Greece over the unlawful deployment of armored vehicles on Aegean islands with demilitarized status.