Liz Truss has been warned that exploring new drilling sites for oil and gas in the North Sea would not help with current energy bills, following reports she plans new licences as one of her first acts if she becomes Prime Minister.

Greenpeace warned new oil and gas could take 25 years to pump out and “have no real impact on energy bills”, while exacerbating climate change.

Ms Truss would invite applications for drilling licences to explore new fields in the North Sea if she becomes prime minister, as well as push oil and gas firms to invest in their existing sites to maximise production, according to The Times.

The newspaper reported that as many as 130 licences could be issued under the plans.

New oil and gas could take a quarter of a century to pump out, will be eventually sold at global prices, and have no real impact on energy bills, yet still fuel the climate crisis

Business Secretary Kwasi Kwarteng, who is likely to be appointed Chancellor if Ms Truss enters No 10, and Brexit opportunities minister Jacob Rees-Mogg, have reportedly been holding talks with oil and gas giants to secure energy supplies amid fears of shortages this winter.

The Government said the meetings were organised to discuss how it could potentially support companies to increase energy supplies and reduce consumer costs. Ms Truss’s team said they were unrelated to her campaign.

Another licensing round was already expected for the autumn, according to the Government’s energy security strategy, published in April.

The strategy says: “The North Sea Transition Authority plans to launch another licensing round in the autumn, taking into account the forthcoming climate compatibility checkpoint and the need for energy security. This will mean more domestic gas on the grid sooner.”

Greenpeace UK’s chief scientist Dr Doug Parr said: “Unleashing a North Sea drilling frenzy isn’t a plan to help bill payers but a gift to the fossil fuel giants already making billions from this crisis.

“New oil and gas could take a quarter of a century to pump out, will be eventually sold at global prices, and have no real impact on energy bills, yet still fuel the climate crisis.”

Tessa Khan, director of Uplift, which campaigns for a fossil fuel-free UK, said: “What is shocking about this announcement is that it suggests that she is prepared to give people false hope. New North Sea oil and gas will do nothing to solve the crisis we face.”

Labour Party chairwoman Anneliese Dodds said issuing more drilling licences in the North Sea is not the answer to the current energy cost crisis.

Asked about Ms Truss’s reported plans, Ms Dodds told Times Radio: “No, it’s not, and the answer really is to be taking action to get the cost of those bills down.”

Meanwhile, Green Party MP Caroline Lucas questioned how increasing oil and gas extraction aligned with the known risks of climate change.

Ms Lucas shared a story on Twitter warning about melting ice in Greenland and warnings of a rise in sea levels, saying: “I assume Liz Truss reads this stuff – but for the life of me can’t imagine how she could possibly conclude that a sensible response to the energy crisis is to extract yet more oil and gas, which is hugely costly and will simply accelerate this massive crisis.”

Mark Ruskell, the environment spokesman for the Scottish Greens, told the BBC Radio 4’s World At One programme that “the best way to isolate Putin is to insulate our homes and to invest in renewables”.

He added: “This won’t make a difference to short-term oil and gas prices because many of these fields won’t be developed for at least a decade, maybe two decades, by which point, unless we have actually weaned ourselves off oil and gas, we will be at a state of climate breakdown.”

An SNP spokesperson said: “Issuing new oil and gas licences does nothing to ease the urgent pressure households across the UK face. They need help right now, and Liz Truss needs to understand the scale of the crisis she is set to inherit.”

Conservative former cabinet minister John Redwood, who backs Ms Truss for leader, said on Twitter: “Good news that Liz Truss plans to get more gas out of the North Sea to ease the squeeze. More permits and some changes of rules can boost output. The answer to an energy shortage and sky high prices is more supply.”

The Truss campaign would not comment on the reports when contacted by the PA news agency, but it pointed to the Foreign Secretary’s previous remarks about using reserves in the UK.

“I also want to make sure we’re exploiting all of the gas reserves and the capacity we have in the UK,” Ms Truss told a hustings in Darlington this month, adding “it is important we increase the supply of energy, and there are more resources to be used in the North Sea”.