The Black Sea should be made, like the Baltic Sea, a NATO sea, with a comprehensive security system developed for all countries in the region, Ukraine’s foreign minister Dmytro Kuleba said on Thursday.

In a speech at the Black Sea Security Conference in Bucharest, Romania, Mr Kuleba noted that the West did not have a sustainable Black Sea strategy, while Russia’s has always been "aggressive, revanchist, and barbaric".

He recalled Russia's first attack on Ukraine's territorial integrity, which took place on the island of Tuzla, between the Black and Azov Seas.

"When fear closed NATO's doors to Ukraine and Georgia in 2008, Russia quickly responded by attacking both," Ukraine’s foreign minister stressed, adding a number of global leaders decided that the best strategy was to "keep the maniac happy", including leaving his potential victims defenceless.

He called on NATO countries to "correct the mistake" at the summit in Vilnius later this year.

"We all now understand that fear is not a strategy. The time has come to develop a comprehensive security system for all states in the region that are frightened by a maniac on the loose," Mr Kuleba said.

"It is time to make the Black Sea what the Baltic Sea has become: a NATO sea. This war has proved that the security of the region is indivisible – a threat to someone is a threat to everyone."

Ukrainian officials have long floated the idea of returning Crimea from Russian occupation as early as by the end of the year.