Playing down the significance of a new nuclear reactor being built by Pakistan, the Bush administration has said the new facility will produce far less plutonium than was reported by an independent think tank.

"The reactor will be over 10 times less capable" than the Institute for Science and International Security's report estimates, State Department spokesman Edgar Matthews said, admitting that Pakistan appears to be diversifying its ability to produce fissile material for nuclear weapons.

He told the Washington Post daily that the new reactor would not be subject to international monitoring and inspection.

The existence of the new Pakistani nuclear reactor under construction was first reported in The Washington Post and was based on analysis provided to the paper by the ISIS.

The initial reaction of the administration was that it was aware of the goings on in Pakistan for sometime.

The report and the analysis came two days before the House of Representatives took up the Indo-US civilian nuclear deal and was perhaps meant to make an impact on the debate and vote in the context of a South Asian nuclear arms build-up.

The House voted overwhelmingly for the agreement.