The Minister of State in the Prime Minister's Office said that together 21 nuclear power reactors, with an installed capacity of 15,700 MW are under implementation and envisaged for progressive completion by 2031.

Besides, in-principle approval has been given for five sites for setting up nuclear plants, he said during the Question Hour.

These sites are in Jaitapur (Maharashtra), Kovvada (Andhra Pradesh), Chhaya Mithi Virdi (Gujarat), Haripur (West Bengal) and Bhimpur (Madhya Pradesh).

To a query on whether the government was considering increasing the capacity of the existing nuclear power plants, Singh replied in the negative.

"The existing units are operating at their rated capacity. The unit size of indigenous Pressurised Heavy Water Reactors (PHWRs) has already been increased from 220 MW to 540 MW and then to 700 MW, which is now under construction.

"In addition, Light Water Reactors of 1,000 MW have also been introduced with foreign cooperation," the minister said.

Singh also said the government has taken several measures to enable setting up of nuclear power reactors.

These include resolution of issues related to Civil Liability for Nuclear Damage Act and creation of Indian Nuclear Insurance Pool, he added.