Professor S S Jha, Director, Tata Institute of Fundamental Research (TIFR), says that American scientists have been visiting and continue collaborating with their Indian counterparts as before.

Reacting to The Indian Express story on eight scientists being denied by the US Government to attend a week-long international workshop at TIFR here, Prof Jha said that a majority of the US scientists who registered to attend the conference have arrived and are participating in the sessions.

A participant from the US brushed aside the denial episode as a minor aberration and said their government was relaxing the conditions for purely academic exchanges.

When asked about the denial episode, he said, ``This is not something unusual or a serious crisis. It was expected.After the May tests, the US Government had imposed sanctions against some Indian institutions and suspended all technical collaborations. That situation continues. The US decision to not allow their scientists to attend this conference is in accordance with that policy decision,'' he said.

``However, a majority of the US scientists who registered for attending the conference have come. It only a few who have not been able to make it,'' Jha said. And the few, it is learnt, belong to laboratories like Fermilab and Argonne National Laboratory, which are funded by the US Department of Energy.

Chairman of the conference, Dr N K Mondal, said visa was obtained for a Pakistani scientist. ``He was not able to attend the conference because of sickness,'' he said.

The TIFR director said India had not imposed any sanctions against visiting scientists and added that many such conferences and lectures have been going on, unhindered, with participation from foreign scientists including those from the US.

Theweek-long conference on Hadron Collider Physics has gathered here to discuss some of the frontline research in particle physics carried out in different labs and universities worldwide. Sponsored jointly by India's Department of Atomic Energy and the Italy-based Abdus Salam International Centre for Theoretical Physics, the conference will be addressing various issues relating to colliders and theories which attempt to explain the apparent diversity of nature. Nearly 130 delegates from 12 countries are attending the conference.