Russia denies breaking rules over low pass of US destroyer

Russia says it observed all required safety measures when its aircraft flew close to a US warship in international waters of the Baltic Sea on Monday.

According to Russia's defence ministry, the Su-24 fighter jets "turned away in observance of all safety measures" after observing the USS Donald Cook.

The ship was sailing close to a Russian navy base, the ministry said.

Russia was criticised over the flybys, which a US official called "one of the most aggressive acts in recent memory".

The two Russian jets flew over the US destroyer almost a dozen times, American officials said.

At one point the jets were so close - about 9m (30ft) - that they created wakes in the water around the ship.

The jets had no visible weaponry and the ship took no action.

The Russian defence ministry said: "After spotting the ship, Russian pilots turned away from it in full compliance with safety measures.

"All flights of the Russian aircraft are in strict compliance with international rules of the use of air space above neutral waters."

The Russian Sukhoi Su-24 aircraft made very low passes by the USS Donald Cook

A Russian Kamov KA-27 Helix surveys USS Donald Cook on 12 April 2016

The commander of the Donald Cook described the flights as a "simulated attack".

The passes were "unsafe, potentially provocative" and "could have caused an accident," officials said in a release.

The actions of the Russian jets may have violated a 1970s agreement meant to prevent dangerous incidents at sea, but it is not clear whether the US is going to protest.

A Russian helicopter taking pictures also passed by the ship seven times.

Analysis: Gary O'Donoghue, BBC News Washington

The jets were so close they created wakes in the water near the ship

These close encounters of a military kind between the US and its allies and Russia have escalated significantly over the past two years, ever since Russia's annexation of Crimea and the substantial break down of relations between East and West.

They take various forms. They can be violations of national airspace; narrowly avoided mid-air collisions, close encounters at sea and simulated attack runs.

The incidents have taken place over a wide area - in and around the Baltic states; in the Baltic sea; the Black Sea and even close to Stockholm, when the Swedish authorities believed a Russian submarine had violated its territorial waters in 2014.

They are regarded by defence analysts as a flexing of muscle - a reminder that Russia has military might and cannot be pushed around.

But the frequency of such situations means many fear that a full on confrontation - be-it deliberate or accidental - is just a matter of time between the world's two great military powers.

The Donald Cook was conducting deck landing drills with an Allied military helicopter when the jets made their passes, according to a statement from the United States European Command.

The US suspended flight operations from the ship until the Russian jets left the area.

The next day, a Russian KA-27 helicopter flew circles at low altitude around the ship, followed by more jet passes.

The aircraft did not respond to safety warnings in English or Russian.