Kissinger told the private New Delhi Television channel that Nixon's reference to Gandhi as an "old witch" -- a comment revealed earlier this week in transcripts of Oval Office tapes and newly declassified documents -- was "Nixon language."
"This was not a formal conversation. This was somebody letting of steam at the end of a meeting in which both president Nixon and I were emphasizing that we had gone out of our way to treat Mrs Gandhi very cordially," Kissinger, 82, told NDTV.
"There was disappointment at the results of the meeting. The language was Nixon language."
Kissinger's comments came after an Associated Press story on the transcripts became front page news across India. But it barely created a ripple in India-US ties, which have improved dramatically in recent years.
Kissinger said the November 5, 1971 conversation had to be viewed as a reflection of Cold War ties, when India leaned toward Soviet Russia.
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At the time, Gandhi was also seen as keen for a military conflict with Pakistan that the United States was trying to avoid. The war did take place a month later, leading to the creation of the new nation of Bangladesh.
The transcript of the Nixon conversation, which took place in the Oval Office, was declassified last week.
"We really slobbered over the old witch," Nixon told Kissinger a day after the president had met Gandhi. Kissinger was then the national security adviser.
"The Indians are bastards anyway," Kissinger had told Nixon. "They are starting a war there ... While she was a bitch, we got what we wanted
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On Thursday, Kissinger said the remarks did not reflect US policy of the day.
"I regret that these words were used. I have extremely high regard for Mrs Gandhi as a statesman," Kissinger said. "The fact that we were at cross purposes at that time was inherent in the situation but she was a great leader who did great things for her country."
Relations between India and the United States are now far removed from Kissinger's days. The two counties are allies with swiftly growing trade and military ties. Increasing US influence is also seen as having influenced Pakistan to act against separatist Islamic militants who have waged attacks in India's Kashmir region since 1989.
"The US recognizes that India is a global power, that it is a strategic partner of the US on the big issues," Kissinger said. He said that both countries' experiences with terrorism had helped bring them together.
Still, the remarks by Nixon and Kissinger, captured by a taping system Nixon had secretly installed in the Oval office, stirred anger in India.
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"It is shocking that the head of state of a country and his principal adviser chose to use such intemperate language against a popularly elected prime minister of another country," said Anand Sharma, spokesman of the Congress party, which leads the ruling coalition.
"The remarks were not only distasteful, they were unbecoming of any head of state. The damning of the entire people of India is unacceptable in any civilized dialogue between countries and people," Sharma said.
"These words have no relevance today ...We hope the present US leader also rejects these remarks which were definitely in very poor taste."