This comes after a high-level conference on disarmament here on Thursday, addressed by UN General Secretary Ban Ki Moon, asked India and eight other countries to ratify the agreement so that it comes into force.

"India has taken a position and we don't see any reason for changing our stand, Krishna told journalists.

"We have taken a principled stand and and so the question of India revisiting it stand depends on a number of other developments that would address our concerns," he added.

Earlier, Moon said that "the CTBT is a fundamental building block for a free world of nuclear weapons".

"By establishing a global norm against testing, the CTBT has made a significant contribution to the world community's efforts to prevent the proliferation of nuclear weapons and to promote nuclear disarmament," he added.

But Krishna responded by saying, "India's stand remains unchanged. We have spelt out why we our unable to sign the pact as it is".

During the occasion, the Moroccan Foreign Minister and chair of the conference Taib Fassi-Fihri said, "We will continue to work with very hard to convince others to join us".
Without directly referring to India and Pakistan, he noted, "I am sure that some countries living in some specific areas with some political problems will join us and we will ask them to join us because it is important for peace and security."

In a meeting chaired by US President Barack Obama, the Security Council has unanimously passed a nuclear non proliferation resolution.

It also calls upon all states to "refrain from conducting a nuclear test explosion and to sign and ratify the Comprehensive Nuclear Test Ban Treaty (CTBT) to bring it into force early."

Russia and the United States have also committed to a new agreement to reduce nuclear war heads and launchers.