The Romanian Navy has wrapped up its largest maritime training exercise of the year, known as “Sea Shield 25.” This massive event, held in the Black Sea, involved over 1,600 troops, dozens of ships and aircraft, and close coordination between twelve NATO countries. The drills took place in early April and ended on April 11, 2025.

The exercise aimed to test how fast and how well NATO forces can react to modern threats. These included attacks from the air and sea, cyber warfare, and chemical dangers. The goal was to boost cooperation and show strength on NATO’s eastern sea border — an area that has grown more tense due to the war in Ukraine and Russian military presence.

NATO Allies Work Together in the Black Sea

Twelve NATO countries joined the event, including Albania, Bulgaria, Canada, France, Greece, Italy, the Netherlands, Spain, Turkey, the United Kingdom, and the United States. These allies worked closely with Romanian forces during the twelve-day drill. Warships, helicopters, and patrol planes filled the skies and waters around the Romanian coast.

Crews carried out live-fire missions, search and rescue exercises, and intelligence-gathering drills. Troops practised spotting enemy submarines, handling radar jamming, and boarding suspect vessels.

At one point, about 64 kilometres off Romania’s coast, radar stations picked up an unidentified flying object. A Puma Naval helicopter was quickly sent to investigate. Air support went on alert, and fleet commanders ordered an emergency response drill. This event, though staged as part of the training, helped test real-time reactions under pressure.

Focusing on Sea Mines and Chemical Threats

Part of the training focused on underwater dangers, like sea mines — which have become a growing concern in the Black Sea. NATO’s Mine Countermeasures Task Group worked together to detect and neutralise these threats.

Lieutenant-Commander Cătălin Harabagiu, a Romanian Navy officer, explained how sea mines can float into busy shipping areas. He stressed that teamwork between allied forces is key to keeping everyone safe.

The drills also included training for chemical, biological, radiological, and nuclear (CBRN) threats. Combat divers and special forces practised entering contaminated zones, checking for chemical agents, and carrying out boarding missions under risky conditions. These simulations aimed to teach troops how to stay calm, act fast, and follow joint tactics in dangerous settings.

Real-World Scenarios with Real-Time Stress

NATO units faced fast-moving drills that mirrored the types of crises they could face in real life. From electronic warfare to sudden air attacks, teams had to stay sharp and work as one. Crews trained to act in close spaces, under tight deadlines, and with limited gear. These tasks helped build discipline, focus, and teamwork.

Commanders watched closely as their units moved through layers of threats. Some drills focused on stealth. Others called for rapid escalation, where a simple patrol could turn into a full-scale attack scenario. This tested how well each team could handle change.

The joint drills showed how much NATO values strong ties and fast action. As Rear-Admiral Cornel Cojocaru put it, “In this region, readiness is not an option. It’s a must.”

Call for More Investment and Upgrades

Admiral Cojocaru, who led parts of the operation, spoke openly about the threat posed by Russia in the Black Sea. He noted that Russia continues to use submarines, aircraft, and surface ships to strike Ukraine and intimidate NATO partners.

He said that Romania must keep upgrading its fleet, buying modern tools, and training at the highest level. “We need better ships, better systems, and top training. The threats are growing, and we must grow with them,” he said.

The admiral also pointed out that “Sea Shield” has grown year after year. Since its launch in 2015, it has become one of NATO’s biggest sea drills. This year’s edition gave partners a chance to share knowledge, test ideas, and build stronger networks.

A Message of Unity and Strength

The 2025 Sea Shield exercise ends at a time when NATO’s unity is more important than ever. With war still raging in Ukraine and tensions rising in the Black Sea, drills like this send a message: NATO is ready to defend its allies.

Crews left the exercise with improved tactics, stronger ties, and a better understanding of how to face modern-day threats together. Many say the exercise will help shape NATO’s next steps in maritime safety and combat readiness.