Pakistan, which is expected to get the first delivery of two F-16 fighters by the year-end, has said that it was negotiating with the United States for 75 more aircraft.

"Pakistan should be getting two F-16s by December and a number of stages have passed ever since Washington approved the sale of F-16s to Pakistan early this year, and things have moved smoothly on this front," Pakistan's Ambassador to the US Jehangir Karamat said.

Right now the exact configuration, cost and numbers are being negotiated between the two countries.

"We are looking at something like 75 F-16s," he told Pakistan's official news agency APP.

Pakistan has around 32 F-16s made in the 1980s, which continue to be its mainstay and hopes to refurbish its fleet with a combination of new and serviced F-16s. The package of 75 F-16s was expected to cost around three billion dollars.

Commenting on the recent US-India defence agreement, Karamat, a former army chief, said Pakistan was carefully analysing it and "Islamabad has its own relationship with the US, which is independent of the relationship the US has with India."

About US-India civil nuclear cooperation, he said the deal has to pass through certain stages like approval by the US Congress followed by enactment of legislation.

"Those things are going to take time and we will see how it goes."

Pakistan does not want any upset in the balance of power between the two states, "as then, Pakistan has to inevitably take steps to redress that (an imbalance).

"I think, this is an accord, which sort of, sets the criteria which a state has to meet to be eligible for such a cooperation with the US," Karamat said.