NEW DELHI — India said on Thursday it will lodge a diplomatic protest with the United States after its ambassador was frisked at an airport reportedly on grounds that she was wearing a "sari".

Last week, India's envoy to the United States, Meera Shankar, was pulled out of the security line at a Mississippi airport and subjected to a "rigorous pat down", according to Indian officials, despite her diplomatic status.

"Let me be frank. This is unacceptable to India. We are going to take it up with the government of the United States so that such unpleasant incidents do not recur," India's Foreign Minister S.M. Krishna told reporters in New Delhi.

In September, Shankar suffered a similar experience at a Chicago airport.

Some Indian newspaper reports said the ambassador was singled out at the airports on both occasions because she was wearing a sari, a traditional draped Indian dress.

Protocol normally exempts diplomatic envoys and other dignitaries from such searches.

"There are well-established conventions, practices as to how diplomats are treated. I am surprised at the way our ambassador has been treated for the second time in three months," Krishna said.

The US embassy in New Delhi said it had no comment on the incident at the Jackson-Evers International Airport.

However, the Times of India quoted Mississippi Lieutenant Governor Phil Bryante as saying he regretted "the outrageous way Indian Ambassador Shankar was treated" by the Transport and Security Administration.

Last year, America's Continental Airlines apologized to former Indian president Abdul Kalam for frisking him before he boarded a flight to the US.