Washington, May 1 (IANS) The landmark India-US civil nuclear deal giving New Delhi access to nuclear technology despite its refusal to sign the Nuclear Non-Proliferation Treaty (NPT) would not weaken the pact, says a top US official.

"We don't believe we weakened the NPT in our peaceful civilian nuclear deal with India," Ellen Tauscher, Undersecretary of State for Arms Control, said in a tele-conference with reporters Friday ahead of the NPT review conference Monday.

"It's a deal that comes with safeguards, and it comes with a number of other transparency mechanisms that we think, frankly, add to the security and the non-proliferation concerns that we had prior to that," she said.

At the instance of the US, the Nuclear Suppliers Group (NSG) has given an exemption to India, which has consistently refused to sign the "discriminatory" treaty, to resume nuclear commerce.

Officials of more than 180 countries will gather in New York next week for the NPT Review Conference held every five years.

Tauscher also expressed disappointment that Pakistan, which too has declined sign the NPT, is blocking negotiations on the Fissile Material Cutoff Treaty.

"I will tell you that I think everyone shares the disappointment that the United States shares, that there is a country (Pakistan) that is blocking the programme of work that was a very hard-fought agreement," she said.

A day earlier addressing the Centre for American Progress, a Washington think tank, Tauscher said that NPT regime is under great stress and US will work to prevent countries from cynically violating the nuclear treaty and then exercising their withdrawal rights to evade accountability.

Accusing countries like North Korea and Iran of violating their international responsibilities under the NPT, she said: "The nuclear non-proliferation regime is under great stress and is fraying at the seams."

"Iran poses another challenge to the nuclear non-proliferation regime. Under the guise of a purportedly peaceful nuclear programme, Iran has violated its IAEA safeguards and Security Council obligations in pursuit of a nuclear weapons capability," she said.

"This cynical path to a nuclear weapon cannot be allowed to serve as a model for others," she said.

NPT state parties enjoy the right to the benefits of the peaceful use of nuclear energy, Tauscher said. "The pursuit of that right cannot be used as a convenient cover for acquisition of nuclear weapons."