The United States on Thursday said that if India conducts a nuclear test, Washington could stop civil nuclear co-operation with New Delhi [Images] but that can happen only after discussions are held to determine the justification for the test.

US Ambassador to India David Mulford said India as a sovereign nation can and will always have the right to go for a nuclear test. But if India does so, under US laws there could then be a cessation of civil nuclear relationship.

"There is a Hyde Act requirement. But in the 123 agreement, which was negotiated to effect that into reality, there is a set of procedures laid down. This involves first of all the president determining that we should enter into a dialogue to discuss why tests were conducted," said Mulford.

As there are certain waiver authorities granted to the US president under the Hyde Act, "in that dialogue reasons just might be found to justify the test. There might be developments in the neighbourhood or something like that could justify the test," Mulford said.

"So certain things can be waived or in fact co-operation could be restored. So cessation is not final. The procedure is detailed in the 123 agreement. So, that is how we govern this relationship," he added.

Asked if the NSG waiver allows India to do nuclear trade with any other countries, Mulford said, "India does not intend to go ahead with any other arrangement until the 123 process is completed."

"We have always understood that the safeguards agreement which India negotiated with the International Atomic Energy Agency, will be signed and activated only after the 123 agreement is passed (by the US Congress). So, we regard that as the present situation," Mulford told NDTV.