Prime Minister Fumio Kishida has moved to restore Japan’s status as a nuclear-powered nation for the first time since the 2011 Fukushima crisis, accelerating the restart of reactors and signalling the construction of new plants.

Kishida’s decision to throw his political weight behind the nuclear power sector is intended to rein in soaring energy costs for households and companies and to support Japan’s nuclear technology manufacturers.

“As a result of Russia’s invasion of Ukraine, the global energy situation has drastically changed,” Kishida said on Wednesday.

“Whatever happens globally, we need to prepare every possible measure in advance to minimise the impact on people’s lives,” he said, adding that the government would aim to come up with concrete plans for the nuclear sector by the end of the year.

The plan to research the construction of new nuclear reactors, which experts say could be safer than those using existing technologies, marks a U-turn in government policy since the Fukushima crisis.

The prime minister had already announced the restart of some nuclear plants after Tokyo came close to suffering a power blackout this year. With the acceleration, it will aim to bring back 17 out of a total 33 operable reactors by summer next year and also to extend the life of existing plants.

Hopes for a nuclear revival sent shares in Tokyo Electric Power Co, the owner of the three reactors that melted down in Fukushima, up 10 per cent, while those of nuclear supplier Mitsubishi Heavy Industries rose 6.9 per cent and Japan Steel Works climbed 5.5 per cent.

No new nuclear plants have been built in Japan since the 2011 disaster, when the largest earthquake in the nation’s recorded history led to the meltdowns at the Fukushima Daiichi plant.

The big increase in global energy prices largely driven by the Ukraine war has made other countries reconsider energy policy, notably Germany, which is rethinking its plan, decided in the aftermath of Fukushima, to exit nuclear power by the end of this year.

Japan’s energy policy has been largely paralysed since the 2011 disaster prompted the shutdown of most of its nuclear reactors. That has forced Asia’s largest advanced economy to burn additional coal, natural gas and fuel oil even as it pledges to achieve net zero carbon emissions by 2050.

Because Japan imports most of its energy, it has also been hit hard by the rise in commodity prices. The country relies on Russia for about 9 per cent of its liquefied natural gas.

“Now is the perfect time to do this,” said Tom O’Sullivan of energy consultancy Mathyos, noting that Kishida did not face any major election for the next three years. “Japan is already paying more for electricity than most other Group of Seven countries, so industrial competitiveness is an issue as well.”

Before Fukushima, Japan sourced about a third of its electricity from its nuclear reactors. Now, only six are operational with restarts hampered by a string of safety incidents and a deep public distrust of Tepco and other power companies.

Restarting the nuclear plants has been an intensified focus of lobbying by Japanese companies this year, according to people directly involved. The Tokyo blackout threat and the Ukraine war were a big part of widening the number of companies involved, they said, though many had actually begun their calls for a restart after the 10th anniversary of the Fukushima crisis.

“There was a feeling that enough time had passed and that the public would be more worried about energy supply than the nuclear risk,” according to a person close to the policymaking unit of Kishida’s ruling Liberal Democratic party.

But the same person noted that local resistance would still be strong, so it was probably premature to assume that all 17 available reactors would be turned back on. Local elections around the country in the next few years would show public opinion on nuclear power, he said.

The geopolitical situation has increased the urgency of Japan’s need to develop new and safer nuclear reactors, said Frank Ling, chief scientist at the Anthropocene Institute.

Kishida could also be aiming to extend Japan’s competitiveness in the sale of nuclear technologies, Ling said, “especially in south-east Asia where there is a severe need for energy development”.