Sen told rediff.com, "It is below our dignity to comment on this incredible ignorance and arrogance betrayed by the intemperate and uncivilised remarks of the Congressman from California."

During a hearing on the US-India nuclear agreement on September 8, Lantos had said, "My concern does not relate to the administration. My concern relates to the insentivie thinking that I see coming out of New Delhi." He added, "It is incomprehensible to me that people as sophisticated and knowledgeable as our Indian counterparts should not be aware of how significant their position vis-�-vis Iran is to this Congress."

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"Only an imbecile would believe that they are developing a nuclear program for peaceful purposes and it is an insult to the intelligence of Congress that they keep repeating this," Lantos had said, but then added, "They do what they do but to have the Indian foreign minister (with respect to his recent meeting with the Iranians) to say they really don't care about what we think, shows the real denseness that occasionally very intelligent people are burdened with."

Lantos asserted, "They are brilliant and they are dense.They are brilliant, which is obvious, but they are simply dense because they are incapable of comprehending that other countries have their important concerns."

He then belaboured the point, saying he found Natwar Singh's reported statement in Iran, 'sickening-literally sickening. This Stalinist rhetoric which we don't accept from the Indian foreign minister' and went on to warn that 'this pattern of dealing with the US will not be productive for India and they have to be told this in plain English that this great opening is predicated on reciprocity'.

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Lantos added if New Delhi did not support Washington's efforts to ostracize Tehran, 'the goodwill will dissipate'.

The lawmaker, quoting from a report, said that during his meeting with the new Iranian president, Natwar Singh had said that India 'supports the resolution of Iran's nuclear issue with the International Atomic Energy Agency framework but opposes sending the file to the United Security Council'.

Senior Indian diplomatic sources told rediff.com that what was particularly galling was that Lantos could have made these remarks, issued these threats and personally attacked Natwar Singh without verifying the credibility of the report, arguing that the foreign minister had never made these remarks attributed to him.

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One senior source said he had immediately called Natwar Singh and checked with him about his purported remarks in Tehran and the foreign minister had said, "What utter nonsense. I didn't say anything of the sort."

The Indian diplomatic sources, who were seething with anger over Lantos' tirade, were particularly incensed that he had personalised it. They said, "All these words - imbecile, dense - you don't use them about a foreign minister."

"No country is going to take this kind of abuse. There must be some semblance of decorum," they said. "Any criticism is perfectly alright and it is a part of parliamentary discourse that you have differences. In our country, we welcome this. In fact, it's part of our tradition."

The sources continued, "You have discourse, dissent and debate, but it should be carried out with a certain mimimum amount of decorum. You can express a viewpoint but don't use such language and personalise it in this manner."

The senior source said, "We won't take it from any congressman or anybody in this or any other country. No self-respecting country will take this kind of language from anyone."

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According to the sources, Lantos' remarks and direct threats were unfortunate because 'we are pushing this relationship so much and we are seeing results and there is so much courtesy (in US-India interactions) at all levels and we never stoop to this kind of thing.'

One source said, "When I was told about it, I was horrified. In fact, the first time I couldn't believe it, but then I read the transcript and I said this is just horrible."

"If he is under any illusion that we are going to flinch under this kind of thing, they are living in another world," the source added.