ATHENS — Adding to fears of a conflict with tension rising over who has rights to the seas, a Greek navy helicopter attempted to stop and check a cargo ship accompanied by Turkish frigates in the Eastern Mediterranean but left after a Turkish military warning.

A Turkish official, speaking on condition of anonymity, told the London-based online news outlet Middle East Eye that incident wasn’t a close one and didn’t put any lives in danger and the Greek Navy didn't respond.

“Greek ships left as soon as they saw the Turkish frigates,” the official said. “They were miles away anyway.”

CNN Greece, which first reported the incident, said the frigate Spetsai approached the Tanzanian-flagged Cirkin on suspicion of carrying weapons to Libya where Turkey backs a United Nations-recognized government but Greece supports rebels.

Greece has denounced a deal Turkey signed with Libya dividing the seas between them, claiming waters off Greek islands and with Turkish President Recep Tayyip Erdogan saying Turkey will drill for energy off Crete.

The report said a Greek ship nearby was under the command of European IRINI operation, which was set up by the European Union in February to stop arms imports to Libya in accordance with the UN weapons embargo.

“The Italian Commander of the European force ordered the Commander of the Greek frigate to take off (sic) a helicopter and control the ship,” the report said, adding that the ship was near Crete's southwest coast.

“As soon as the Greek helicopter approached Cirkin, it received a call from a Turkish frigate that sent the message that 'the Turkish ship is under the protection of the Turkish republic,'” the report added.

After the radio message, the Italian Commander ordered the Greek helicopter to return because IRINI doesn’t have authorization to intervene with vessels accompanied by ships belonging to third countries, according to the report.

Despite the UN weapons embargo, Turkey signed a military cooperation deal with Libya and sent drones, armored vehicles, Syrian mercenaries and military officers to support the government against the forces of eastern-based commander Khalifa Haftar.

That put the UN in the awkward position of supporting the government in Libya but opposing sending arms there.