A US aircraft is already patrolling over the Black Sea to look for threats, prime minister Rumen Radev said in Tvarditsa. He said this followed his talks with NATO and Bulgaria's partners.

"It has already started patrols over the Black Sea to gather intelligence and spot any activity that could be a risk," Radev said. How long the aircraft stays depends on the situation. He expects more help too.

Radev also spoke about the drone attack on the Chelsea-3, where debris has been found. Investigators are studying the physical remains of the drones and running chemical tests to find out what explosive was used.

The prime minister said the debris should show whose drone it was. He hopes to learn its type too. Allied teams with high-tech equipment arrive tomorrow to help with this.

Radev denied there are problems with merchant ships. He said the ships have not stopped sailing.

He does not think Bulgaria risks unrest like the protests in France and Italy. He said that is still far from Bulgaria, and that Europeans have taken to the streets for a mix of reasons.

Radev also said the war in Ukraine drains economies and leads to social tension and political instability. He said it must end as soon as possible. "It will be harder and harder to explain politically why the wealth of European citizens is draining away in this war instead of solving their problems," he said.

Radev took part in the groundbreaking ceremony for a battery park to store electricity in Tvarditsa. Innovation and digital transformation minister Ivan Vasilev and energy minister Iva Petrova were also there.

In October we reported that military prosecutors and the Interior Ministry's counter-terrorism unit were examining the Chelsea-3 at the port of Burgas. They are looking for traces of the drones that hit the ship and trying to find out what explosive was used.

Radev said the park will bring huge benefits to the region and to Bulgaria, because it will use the most modern technology in the world. He said Bulgaria is already established as a European leader in energy storage. This brings a number of advantages, including a lower price, he said.