The second unit of the Chashma Nuclear Power Plant in Punjab province, which will produce 330MW of electricity, was completed more than three months ahead of schedule, Gilani told a gathering that included senior military officials and federal ministers.
It is the country's third operational nuclear plant.
"I wish to use the occasion of the inauguration of C-2 (nuclear power plant) to urge the international community to eliminate discrimination between nations and make this promising technology accessible to Pakistan for peaceful use like power generation," he said.
Over the past few years, Pakistan has been lobbying the US and other major powers to give it a civil nuclear deal similar to the one granted to India.
Islamabad has contended that the India-US nuclear deal has affected the strategic balance in the region.
The US has begun negotiations with Pakistan on the issue but made it clear that a nuclear deal could not be cleared immediately due to concerns about proliferation linked to the clandestine ring that was operated by atomic scientist A Q Khan and supplied know-how and atomic technology to countries like Libya and North Korea.
Gilani hailed the new nuclear power plant at Chashma as "yet another illustrious example of the Pakistan-China cooperation in the field of nuclear science and technology".
Despite concerns expressed by the West, China and Pakistan have inked a deal to build two more atomic plants at the Chashma site.
Officials said the two plants were expected to be completed by 2016-17.
Gilani said the two power plants C-3 and C-4 were "already under construction" at the Chashma site and will help the Pakistan Atomic Energy Commission to meet the government- assigned target of generating 8800MW of nuclear power by 2030.
"In fact, I will encourage you to look beyond 2030, say to 2050, and provide Pakistan with far greater capacity than 8800MW. I am sure, you will accept the challenge," he said.
Gilani made a case for Pakistan to be granted access to civilian nuclear technology, saying the country had been operating atomic power plants for over 30 years and needed alternative energy sources like nuclear power to overcome a crippling shortfall of electricity.