Turkish President Recep Tayyip Erdogan and his Russian counterpart Vladimir Putin on Wednesday came together for a tete-a-tete in Sochi in an attempt to find common ground. In other words, they agreed to disagree on a number of crucial issues, including Syria, Ukraine, Afghanistan, Libya, anti-missile batteries and new natural gas deals. The meeting, which lasted for nearly three hours, was considered one of the most critical summits held between these two ambitious leaders, as they face several challenges in their relationship. Ankara and Moscow have long sought to navigate their differences in foreign policy interests, but the Syria and Ukraine files seem to have severely tested their fragile relationship. Although the situation in the northwestern Syrian province of Idlib — where the escalation between the Russian-backed Syrian government forces and Turkish-backed rebels is mounting — was the most contentious item on the agenda, Turkey’s growing support for Ukraine is an equally important matter that has Ankara and Moscow on collision course. The Erdogan-Putin meeting not only came a few days after Turkey admitted that ties with the US were at their lowest point, but also in the wake of Ankara’s rejection of the parliamentary elections held in Crimea, which Russia illegally annexed from Ukraine in 2014. In a statement, the Turkish Foreign Ministry underlined Ankara’s support for Ukraine’s territorial integrity, adding that State Duma elections held in Crimea in mid-September have “no legal validity for Turkey.” Erdogan also reiterated his Crimea pledge during his address to the UN General Assembly — a move that wasn’t welcomed by Moscow and prompted a flurry of angry coverage in the Russian media. Ankara and Moscow have diverging interests over Ukraine, which is tied up in a conflict with Russia over the annexation of Crimea. Turkey was among the first countries to voice support for the Crimea Platform, which was initiated late last year as part of Ukraine’s strategy to clear Crimea of Russian forces. Turkey, which is also involved in the Russian arms trade with its purchase of the S-400 missile defense system, has been laying the foundations for a promising defense cooperation partnership with Ukraine for some time. The two countries are working together on game-changing military developments, such as drone warfare, aerospace engines and missile technology. Moscow has recently urged Ankara to “carefully analyze the situation and stop fueling Kyiv’s militaristic sentiment.” Ankara’s growing support for Ukraine is an important matter that has it on collision course with Moscow. Sinem Cengiz The Ukrainian administration, which also objects to Russia’s elections in Crimea on the grounds that they violate international law, recently announced that it was planning to set up a plant for the joint production of Turkish-made TB2 combat drones. TB2 producer Baykar Defense won a contract, worth $69 million, to sell six TB2s to Ukraine. The company has also sold to countries including Qatar, Azerbaijan and Poland, which became the first EU and NATO member to acquire drones from Turkey. Ankara has invested billions of dollars in its defense industry over recent decades in an effort to expand its share of global defense trade. One of the key drivers of Turkey’s defense sales to Ukraine is obviously to increase its defense exports. However, this is not the sole motivating force behind its close ties with Kyiv. Last week, a short visit to the Ukrainian capital led me to notice the increasing presence of Turkish companies in the country. The main terminal building at Boryspil Airport, which connects Kyiv to the world, as well as the country’s largest stadium and hundreds of kilometers of highways were all built by Turkish construction companies. Turkish companies, which operate across a wide range of fields, including telecommunications, health, construction and food, are considered the largest foreign contractors in Ukraine. It is also important to underline that, besides defense, there are ongoing talks regarding the signing of a free trade agreement between Ukraine and Turkey. The growing ties between Kyiv and Ankara are a matter of concern for Russia, which seems to be one of the most important factors in the foreign policy strategies of both Turkey and Ukraine. Historically and politically, Moscow has been a leading threat perception in both countries. Thus, in terms of regional interests and relations with the West, Russia is always in the picture either as a partner or a threat. Ukraine is a long-standing NATO advocate and a pro-Western former Soviet state in a contested region. Therefore, it is also of strategic importance to Turkey, which has stepped up its efforts to boost ties with Kyiv. Erdogan has given his support to Ukraine’s bid for membership of NATO. Although not an EU member, Ukraine is considered a priority partner for Brussels, which seeks to build an increasingly close relationship that will gradually increase cooperation to cover economic integration and deeper political cooperation. It will be crucial how Ankara walks the fine line in its relations with Russia and Ukraine at a time when it needs to negotiate for a second batch of the Russian-made air defense system and new natural gas contracts. Many of Turkey’s gas contracts expire by the end of this year, five of them with Russian energy companies, including Gazprom. It is equally important to see how Russia, which considers the Crimea issue to be critical to its national security and territorial integrity, will navigate its negotiations with Turkey on defense and gas in light of the several contentious issues it has with Ankara. Sinem Cengiz is a Turkish political analyst who specializes in Turkey’s relations with the Middle East. Twitter: @SinemCngz Disclaimer: Views expressed by writers in this section are their own and do not necessarily reflect Arab News" point-of-view