The North Sea windfall tax will imperil UK Government attempts to revive Britain's oil and gas industry, the boss of London's newest energy giant has warned.
Meg O'Neill, chief executive of Woodside Energy, said the Treasury's energy profits levy was a "red flag" showing that Britain was "not a particularly conducive place to invest".
"If the Government has aspirations of reviving the UK oil and gas sector, this is probably not the best way to do it," she told the Times.
Ms O'Neill was speaking as the Australian group prepares to start trading its shares in London through a secondary listing today after the completion last week of its merger with the oil business of BHP to form a £30billion giant.
Woodside was focused on Australia before the deal with BHP, swallowing the mining behemoth's oil assets including in the US Gulf of Mexico and Trinidad & Tobago. Its production is now equivalent to more than 500,000 barrels of oil per day - about 70% of which is gas.
Woodside issued new shares to BHP shareholders, who now own about 48% of the enlarged group, and has taken out secondary listings in New York and London. Ms O'Neill said it had done so both to make it easier for BHP investors to receive its shares, with those in London expected to own about a tenth of the company initially, as well as to access a bigger pool of investors.
The oil and gas industry is under intense scrutiny as Russia's invasion of Ukraine inflates commodity prices, pushing up company profits and household bills.
Ms O'Neill said that "the events in Ukraine are a horrible tragedy", but acknowledged that Woodside stood to benefit from the resulting increase in global demand for liquefied natural gas, which it supplies to customers in Asia.
"What we're seeing in Europe, with Europe trying to get off of Russian gas, is in some ways conducive for our business," she said.
To fund help for UK consumers in response to the crisis the Treasury has imposed a levy on oil and gas producers that has increased the total tax rate in the North Sea from 40% to 65% and could last until 2025.
The Government wants to encourage investment in the North Sea to bolster Britain's energy security and has insisted that the tax hike won't discourage this because of new tax breaks that mean the more companies invest the less tax they pay.
However, Ms O'Neill joins a number of leading oil and gas producers in warning that the tax will nevertheless hit investment.
"One of the things that's most important for us from a government perspective is a stable tax regime," she said.
"When governments change the rules without a whole lot of consultation or engagement, that's a bit of a red flag for us."
While Woodside doesn't have any assets in the UK and wasn't looking to invest in the North Sea in its "base case", the windfall tax made it even more unlikely, she said.
"It sends us a message that this is just a riskier jurisdiction to do business in than we might have previously thought."
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