Tuzla Island emerged as a result of a severe storm in 1925, which separated it from the Taman Peninsula. In 1954, along with Crimea, it became part of the Ukrainian SSR. Following the collapse of the USSR, the status of the Kerch Strait and the Sea of Azov became a subject of constant political disputes. Ukraine insisted that the Strait should be regarded as internal waters and that the state border should run between the Taman Peninsula (RF) and Tuzla (Ukraine). Russia, however, refused to recognize Tuzla as a separate island, asserting that it was merely an extension of the Taman Spit, and demanded joint use of the Azov-Kerch water area, allowing the border to be drawn only along the seabed. On January 28, 2003, a treaty on the land border was signed, but the issue of maritime demarcation was postponed “for negotiations.”

The open crisis began on September 29, 2003, when Russia, without agreement from Ukraine, started the intensive construction of an earthen dam from the Taman Peninsula toward Tuzla. The work was carried out at an extremely rapid pace: hundreds of trucks of sand were dumped daily, builders worked in multiple shifts, and the dam advanced by approximately 150 meters per day. Within a few days, the embankment approached the Ukrainian border to less than 150 meters, and by October 23, it reached within 100 meters of the Ukrainian pontoon post, which could have led to the physical connection of the island with the Russian mainland.

Ukraine’s reaction was the dispatch of an official note of protest by the Ministry of Foreign Affairs, emphasizing a gross violation of the state border. Strengthened units of border guards and marines were urgently deployed to the island, setting up a new fortified border post and establishing a surveillance system. To ensure security in the strait area, Naval Forces were concentrated: ships and boats arrived in Crimea, taking control of the sea approach to the island. On the coast, the Ukrainian side deployed rocket launchers and anti-aircraft means, declaring a heightened state of alert in case of further escalation.

In response, Russia intensified its military presence: Black Sea Fleet warships were deployed into the waters of the Sea of Azov, and combat firing exercises were conducted on the Taman Peninsula, intended to demonstrate a readiness for forceful pressure.

On October 22, 2003, the Verkhovna Rada of Ukraine held an emergency session dedicated to the crisis, highlighting the danger of Russia’s actions to state sovereignty.

On October 23, 2003, direct negotiations between Presidents Leonid Kuchma and Vladimir Putin took place, after which the dam construction was halted. In late October, work finally ceased at a distance of about 100 meters from the Ukrainian border. In December, the Presidents of Ukraine and the Russian Federation signed the “Treaty between Ukraine and the Russian Federation on Cooperation in the Use of the Sea of Azov and the Kerch Strait,” but the key issues of border delimitation remained unresolved. In April 2004, the agreement on the land border was ratified, but the maritime area was never divided. Only in July 2005, following new negotiations, did the RF officially recognize Tuzla Island and its adjacent waters as belonging to Ukraine, although the Russian Foreign Ministry clarified that the “legal status of the island remains undetermined.”

Tuzla remained under Ukraine’s control until 2014. After the occupation of Crimea, it came under the factual authority of the RF, and the supports for the so-called “Kerch Bridge” were laid directly through this island. In April 2018, the occupation administration of Crimea transferred a 6,500 square meter section of Tuzla to Russia, which prompted sharp condemnation from the Government of Ukraine and calls from the international community not to recognize this step.

The events of 2003 were referred to by many Ukrainian and Western analysts as the “Kremlin’s test war” preceding the occupation of Crimea. Ultimately, they demonstrated that Russia was willing to employ hybrid pressure tactics, create artificial conflicts, and act in border areas in a way that would be repeated ten years later in the form of the full-scale occupation of Crimea.