Pakistan's fourth nuclear power plant was inaugurated by Prime Minister Nawaz Sharif on Wednesday, with the leader inviting further Chinese investment in power generation.

The plant, known as Chashma-3, or C-3, has been build with Chinese assistance at Chashma in the Mianwali district of southern Pakistan, where two similar plants are already in operation and another is nearing completion.

The new facility is capable of generating 340 megawatts, while the two existing plants in the area can generate 325 megawatts each.

"I invite Chinese companies to invest in the nuclear power plants in Pakistan," Sharif said during a speech.

He said that providing cheap electricity is one of his main promises to the people of Pakistan, and he hopes to be able to make good on his promise by the next election, set to take place in March 2018.

The government has been working on several power projects, the bulk of which have involved Chinese assistance under the China-Pakistan Economic Corridor scheme.

Sharif said he was personally supervising those projects, to ensure they would be completed on time or ahead of schedule.

As Sharif was speaking at the plant's inauguration ceremony, several parts of Pakistan were subjected to compulsory electricity outages due to power shortage.

Pakistan's first nuclear power plant, the 137 MW Karachi Nuclear Power Plant, was set up in 1972, and is still in operation, albeit at a reduced capacity.

Western countries have put a moratorium on the supply of nuclear power plants to Pakistan due to its nuclear weapons program. However, China has continued to supply nuclear plants to Pakistan, making it the only country to do so.

Two 1,100 megawatt nuclear power stations are being constructed in Karachi, and the Pakistan Atomic Energy Commission has plans to install 8,000 megawatt plants by 2030.