This file photo taken on July 12, 2022, shows British Conservative Party member Rishi Sunak launches his campaign for the Conservative Party leadership in London. (ALBERTO PEZZALI / AP)

Former British finance minister Rishi Sunak, who is competing to be the country's next prime minister, on Thursday set out a plan, including a reduction in energy bills, to tackle rising costs for households.

Writing in The Times, he said every household would get savings of around 200 pounds (US$244) on their energy bills with a reduction in value-added tax (VAT).

The UK is bracing for already high energy bills to more than triple this year, with charities warning that millions of people could be forced into poverty if the government does not launch a multi-billion pound support package to soften the blow.

The UK is bracing for already high energy bills to more than triple this year, with charities warning that millions of people could be forced into poverty if the government does not launch a multi-billion pound support package to soften the blow

Sunak, an underdog in the leadership race behind front-runner Liz Truss, said his plan would cover "support for the most vulnerable, support for pensioners and some support for everyone."

The former finance minister said the most vulnerable group of people and pensioners would get the money to meet their energy costs through the welfare system.

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Sunak also said that he will pay for the plan by driving a program to identify savings across the government. "That may mean we have to stop or pause some things in government."

He added that he is prepared for "some limited and temporary, one-off borrowing as a last resort to get us through this winter."

"Given energy prices continue to rise, it is also likely the government will raise more revenue from the Energy Profits Levy that I introduced," he added, referencing a 25 percent windfall tax on oil and gas producers' profits he previously introduced as finance minister.

Sunak's rival, Foreign Minister Truss, has so far said she favors tax cuts for households, rather than funneling cash back via energy support.

Truss also said on Wednesday that she would work with energy companies to bring prices down if she becomes the PM. Critics say tax cuts would favor the richest over the poorest.

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