The European Union has warned tensions between Russia and Ukraine have reached dangerous levels after the Ukrainian navy claimed Russia’s coast guard rammed and opened fire and seized three vessels in the Black Sea.

Russia’s Federal Security Service (FSB) quickly hit back saying they had evidence that Ukraine was responsible for the clashes between the ships. Russia has accused Ukraine of provoking a response.

The tense standoff happened as the ships sailed off the coast of the Crimean Peninsula, Several Ukrainian crew members were said to be wounded in the incident which involved two small Ukrainian armoured artillery vessels and a tug boat.

Ukraine’s navy said two of the vessels were struck and Russia’s coast guard crews then boarded them as well as the tugboat and seized all three.

Kiev said the three vessels were sailing from the Black Sea port of Odessa to Mariupol in the Sea of Azov via the Kerch Strait. They say Ukrainian authorities had given advance notice to the Russians of their travel plans.

“Russian coast guard vessels … carried out openly aggressive actions against Ukrainian navy ships,” the Ukrainian navy statement said.

It said a Russian coast guard ship damaged the tugboat’s engine, hull, side railing and a lifeboat.

Ukrainian President Petro Poroshenko immediately called a meeting with his top military and security chiefs to discuss the situation.

Meanwhile Russia’s FSB said in a statement: “There is irrefutable evidence that Kiev prepared and orchestrated provocations … in the Black Sea. These materials will soon be made public.”

Russian Foreign Ministry spokeswoman Maria Zakharova said on Facebook that the incident was characteristic of Ukrainian behaviour: provoke, pressure and blame for aggression.

Russia also says the Ukrainian vessels were in its waters and blocked access to the Sea of Azov with a tanker.

THE CRIMEA ISSUE
There have been growing tensions between Ukraine and Russia since Russia annexed Crimea from Ukraine in 2014 and built a giant road bridge linking it to them.

Since then Russia has steadily worked to increase its zone of control around the peninsula.

The latest dispute comes after the countries traded blows over another incident involving the same three vessels.

This prompted Moscow to block the passage through the Kerch Strait with a large tanker.

The Kerch Strait is a narrow body of water nestled between Crimea and the Russian mainland, it links the Black Sea to the Sea of Azov, which is home to two of Ukraine’s most important ports.

As Russia controls Crimea and the linking bridge, it is able to control shipping flows.

This is despite a 2003 treaty which designates the Kerch Strait and Sea of Azov as shared territorial waters.

A witness told Reuters that at least two Sukhoi Su-25 warplanes were seen screeching overhead during the latest incident, and Russian TV claimed combat helicopters had been deployed in the area.

Russia’s coast guard said that the three Ukrainian vessels made an unauthorised crossing through Russian territorial waters.

A spokeswoman for the European Union said “tensions in the Azov Sea and Kerch Strait have increased dangerously” as analysts deemed the ship attack as “naked aggression”.

The incident has already sparked outrage in Ukraine, with angry protesters gathering outside the Russian embassy in Kiev.

Photographers captured smoke flares being thrown in the crowd. The protests attracted a heavy police presence.

“We expect Russia to restore freedom of passage at the Kerch strait and urge all to act with utmost restraint to de-escalate the situation immediately,” The EU’s Maja Kocijančič wrote in a statement.

“As clearly stated by the High Representative at the European parliament recently, the events in the Sea of Azov are a demonstration of how instability and tensions are bound to rise when the basic rules of international co-operation are disregarded.

“The construction of the Kerch Bridge took place without Ukraine’s consent and constitutes another violation of Ukraine’s sovereignty and territorial integrity. It has led, in parallel with the militarisation of the Azov Sea, to tougher controls on naval traffic in the strait. The European Union expects Russia to stop the inspections.

“The EU does not and will not recognise the illegal annexation of the Crimean peninsula by Russia.”

NATO has also commented, saying they’re “closely monitoring” developments in the Azov Sea and the Kerch Strait.

“We call for restraint and de-escalation,” spokeswoman Oana Lungescu wrote on Twitter.

“NATO fully supports Ukraine’s sovereignty and its territorial integrity, including its navigational rights in its territorial waters.

“We call on Russia to ensure unhindered access to Ukrainian ports in the Azov Sea, in accordance with international law.”

Some analysts of the Crimea conflict said the latest attack was an example of Russia’s naked aggression, and called for sanctions in response.

ECONOMIC BLOCKADE
The Kerch Strait is the only passage into the Sea of Azov beyond it. Transit under the Kerch bridge has been blocked by the cargo ship, and dozens of others awaiting passage are stuck.

Russia has not given any indication of how long it will keep the strait blocked off, but a long-term closure to civilian traffic would amount to an economic blockade of Ukrainian cities on the Azov coast. And Russia’s Black Sea Fleet greatly outmatches the Ukrainian navy.

Ukrainian cities on the Sea of Azov include strategically vital centres such as Mariupol — the closest government-controlled city to Donetsk and Luhansk, the breakaway regions of eastern Ukraine controlled by Russia-backed separatists.

FSB: UKRAINE PROVOKED US
Russia’s Federal Security Service, known as the FSB, told Russian news agencies after the first incident that the Ukrainian ships held their course and violated Russian territorial waters.

The FSB accused the Ukrainian navy of staging a provocation against Russia.

Russia says the Ukrainian ships had been manoeuvring dangerously and ignoring its instructions with the aim of stirring up tensions.

“Their goal is clear,” an FSB statement said — “to create a conflict situation in the region.”

The Ukrainian Foreign Ministry said in an earlier statement that Russia’s actions were a violation of the UN Charter and international law, and pledged to “promptly inform our partners about Russia’s aggressive actions.”

“Such actions pose a threat to the security of all states in the Black Sea region,” the statement said, “and therefore require a clear response from the international community.”

US ACCUSED OF ENCOURAGING FIGHT
Dmitry Kiselyov, a commentator on the state-controlled Rossiya channel, told viewers of his evening news program that Ukrainian President Petro Poroshenko — encouraged by the US — is looking to pick a fight with Russia in the Black Sea.

The talk show host also said that the US talked Poroshenko into staging a provocation against Russia as a means to disrupt the upcoming meeting between Presidents Vladimir Putin and Donald Trump at this week’s Group of 20 summit in Argentina.

“What is happening now at the (Kerch) bridge threatens to turn into a very unpleasant story,” Mr Kiselyov warned.

The impact of Russia’s annexation of Crimea is still being felt, so the latest incident threatens a push towards a wider conflict between the two countries.