Explanation:

Turkey is set to implement an international convention on naval passage through two of its strategic straits, which would allow them to limit the movement of Russian warships between the Mediterranean Sea and the Black Sea.

• Turkey said that the situation in Ukraine had become a war, a declaration that authorises Turkey to activate the Montreux Convention and ban Russian war vessels from entering the Black Sea through the Bosporus and Dardanelles straits.

Note: The Bosporus and Dardanelles straits, also known as the Turkish Straits or the Black Sea Straits, connect the Aegean Sea and the Black Sea via the Sea of Marmara. It is the only passage through which the Black Sea ports can access the Mediterranean and beyond.

Montreux Convention

• According to the 1936 Montreux Convention Regarding the Regime of the Straits, often referred to simply as the Montreux Convention, Turkey has control over both the Bosporus and Dardanelles straits.
• In the event of a war, the pact gives Turkey the right to regulate the transit of naval warships and to block the straits to warships belonging to the countries involved in the conflict.
• Russia’s location on the Black Sea complicates the situation. Article 19 of the treaty contains an exception for the countries on the Black Sea that can effectively undermine Turkey’s power in blocking the Russian warships entering or exiting the Black Sea.

Note: Turkey has used the convention’s powers before. During World War II, Turkey prevented the Axis powers from sending their warships to attack the Soviet Union – and blocked the Soviet navy from participating in combat in the Mediterranean.

Hence only statement 1st is correct.