Turkish President Tayyip Erdogan called for an end to what he described as "worrying" developments in eastern Ukraine's Donbas region after meeting with Ukrainian President Volodymyr Zelenskiy on April 10.
The meeting, which lasted more than three hours in Istanbul, was part of a previously scheduled visit but coincided with increased tensions between Kyiv and Moscow over the long-running conflict in eastern Ukraine.
Erdogan expressed his concern about the current fraught situation at a news conference alongside Zelenskiy, adding that he hoped the conflict would be resolved peacefully through dialogue and in line with Ukraine's territorial integrity.
"We believe that the current crisis can be solved with peaceful and diplomatic means on the basis of the integrity of Ukraine and international law," Erdogan said.
Turkey and Ukraine, both of which border on the Black Sea, maintain close relations, and Turkey has previously condemned the Russian annexation of the Crimean Peninsula in 2014.
"As Turkey, we have strongly defended the integrity and sovereignty of Ukraine. We have once more confirmed our decision not to recognize the occupation of Crimea," Erdogan said at the press conference.
During their meeting the presidents also discussed expanding defense cooperation between their countries. Zelenskiy said the stepped-up cooperation would apply especially to weaponry and the construction of fighter jets.
Zelenskiy said Kyiv and Ankara share the same view on threats in the Black Sea region and the response to those threats.
Zelenskiy, who visited troops in the Donbas region two days ago, said he had briefed Erdogan on the situation in detail.
Major movements of Russian armed forces toward or near Ukraine's borders and into Ukraine’s Russian-occupied Crimean Peninsula have been captured in photographs, video, and other data, fueling concerns that Moscow may be preparing to send forces into eastern Ukraine.
The Kremlin has rejected Western calls to pull back its troops, denying they are a threat while adding that military movements within Russia are an internal sovereign issue.
Washington has called Moscow's military buildup "destabilizing," and the White House has expressed concern about the recent troop movements.
U.S. Secretary of State Antony Blinken consulted the German and French foreign ministers on April 9 about the need for Russia to cease its military buildup in the occupied Crimean Peninsula and near Ukraine’s eastern borders.
Russia seized Ukraine's Crimean Peninsula in March 2014, sending in troops and staging a referendum denounced as illegitimate by at least 100 countries.
Since then, overwhelming evidence suggests Russia has continued to lend diplomatic and military aid to armed separatists fighting in the Donbas region.
The conflict has killed more than 13,000 people and displaced more than 1 million since April 2014.