India protested a US Navy warship conducting a patrol in its waters without prior consent, in a manoeuvre Washington defended as an "innocent passage" consistent with international law.
The US Navy said earlier this week that the USS John Paul Jones had asserted "navigational rights and freedoms" in the vicinity of Lakshadweep Islands inside India's exclusive economic zone.
The Navy also said that it did so without prior consent in a challenge to India's "excessive maritime claims" in the area, prompting New Delhi to say on Friday it had conveyed concerns through diplomatic channels.
The Indian foreign ministry cited the UN Convention on the Law of the Sea, saying it did not authorize other states to "carry out military exercises or manoeuvres, without the consent" of the concerned country.
But Pentagon spokesman John Kirby defended the move, saying the Navy destroyer had asserted its navigational rights "by conducting innocent passage through its territorial sea in normal operations."
"...we continue to maintain the right, indeed the responsibility, to fly, sail, and operate in accordance with international law," he said in a televised video briefing.
The spat comes as ties between Washington and New Delhi are on the upswing, bolstered by the so-called "Quad" alliance that also includes Japan and Australia.
The alliance is seen as a bulwark against China, which has been flexing its muscle in both trade and security in the Indo-Pacific region.
Last November, the allies held a strategic naval drill in the Bay of Bengal that involved anti-submarine and anti-aircraft drills.
