HRD Minister Kapil Sibal today disagreed with his ministerial colleague Jairam Ramesh's remarks on IITs and IIMs, saying the faculties of these institutions are "world class".

He said if the IITs have not gained the critical mass to change the global scientific discourse, it is because of the "ecosystem" and not because of the faculties.

"25 per cent of the IIT faculty are students of IITs who have done B Tech. Surely the 25 per cent students who are world class students must be world class faculty," he told reporters here in reference to Environment Minister Jairam Ramesh's remarks that the faculties of IITs and IIMs were not world class.

Without taking Ramesh's name, Sibal said he is entitled to make his comments. The comment made by him must be seen in the light of the general view within the community that the calibre of contributions by the scientific community does not really match world standards, he said.

He said the premier institutes in the country rank among the top 50 in the global index, with IIT Bombay placed at No 21, IIT Delhi at 24, IIT kanpur at 37 and IIT Madras at 39.

In terms of publication too, he said, the rate was 15 to 17 per cent in case of IITs as against the global rate of 4 per cent.

However, noting that the IITs have not gained that critical mass to change the global scientific discourse, he said, "It has something to do with the ecosystem."

"If the US spends USD 250 billion dollars on research, India spends USD 8 billion dollars, you cannot create that critical mass. Thats not because of faculty," he said.