A Russian fighter jet flew within 10 ft of a US aircraft in a “dangerous and unprofessional” manoeuvre over the Black Sea.
Pentagon officials have slammed the intercept by the SU-27 jet, which is taking part in Russia’s military exercises in the area.
However, Russian officials defended the action, stating the US plane had been approaching Russian territory so they had simply adhered to rules.
Pentagon spokesman Capt Jeff Davis said the US Navy P-8A Poseidon aircraft had been conducting routine operations in international airspace when the Russian fighter approached.
"These actions have the potential to unnecessarily escalate tensions, and could result in a miscalculation or accident," he said.
It is believed the Russian jet had flown within 30 ft of the US plane before closing to just 10 ft (3 metres).
Relations between the two nations have been strained since Russia annexed Crimea from Ukraine in 2014.
In April this year, the US claimed Russian jets had confronted its planes over the Baltic Sea, again in as “unsafe and unprofessional” manner.
The two leaders, Barrack Obama and Vladimir Putin, were photographed in a tense confrontation at the recent G20 Summit in China.
