The Kudankulam project was not something new and had been started many years ago and work on it is currently in progress, he said, adding it cannot be "accepted if they rake up the issue now."
"Indian government will do what is required," he told reporters at his residence before leaving for the assembly to sign the MLA`s register.
His remarks came a day after Colombo voiced concern over the possible impact of radiation from India`s nuclear power plants in the southern region, as it prepares to raise the issue with global atomic watchdog IAEA.
"We respect the right of India to have nuclear power stations. But our concerns are on the possible radiation affects they could have on Sri Lanka. We have already written a letter", Sri Lanka`s power and energy minister Champika Ranawaka had said.
Kudankulam nuclear plant in India`s Southern coast is just 250 km from Sri Lanka`s northwest coastal town of Mannar.