Pakistan Tuesday said it opposed a new nuclear deal signed between the US and India during a recent trip to New Delhi by President Barak Obama, saying it was detrimental to stability in South Asia.

The US and India reached an agreement Sunday during Obama's visit to New Delhi, breaking the deadlock that has stalled a civilian nuclear power agreement for years.

The US and India in 2008 signed a landmark deal giving India access to civilian nuclear technology, but it had been held up since by US concerns over India's strict laws on liability in the event of a nuclear accident.

"The operationalisation of Indo-US nuclear deal for political and economic expediencies would have a detrimental impact on deterrence stability in South Asia," advisor to Prime Minister on foreign affairs Sartaj Aziz said in a statement Tuesday.

Aziz described the new deal with India as "another country-specific exemption from Nuclear Suppliers' Group (NSG) rules" that would undermine the credibility of the watchdog, weaken the non-proliferation regime and "further compound the already fragile strategic stability environment in South Asia".

"Pakistan remains opposed to policies of selectivity and discrimination," he added.

He said Pakistan would continue to maintain its constructive engagement with NSG and other export control regimes to build its case for membership.

Aziz also referred to Pakistan's policy on reforms in the UN security Council, saying: "Pakistan favours a comprehensive reform of the Security Council to make this principal organ of the UN more representative, democratic, effective, transparent and accountable".

"A country, in violation of UN Security Council resolutions on matters of international peace and security, such as the Jammu and Kashmir dispute, by no means qualifies for a special status in the Security Council."

Pakistan and India have fought two wars over Muslim-majority Kashmir, which both countries administer in part but claim in full.

Recent exchanges of fire across the de facto border, known as the Line of Control (LoC) have killed more than two dozen civilians and forced thousands to flee their homes on both sides.

Pakistan and India traded blame for the upsurge in firing and shelling which started on October 6 last year.