A refusal to greenlight the Jackdaw and Rosebank projects would mark “the end of the oil and gas sector”, the shadow Scottish secretary has warned.

Harriet Cross warned that a UK Government decision to block the fossil fuel projects could drive energy firms out of the country.

It was reported last month that ministers were ready to approve plans to produce gas from the Jackdaw field, off the coast of Aberdeen.

Mrs Badenoch has used a speech at her party’s conference to fuel speculation the Government is keeping its decision under wraps until after a parliamentary by-election later this week.

Speaking at the Conservative Party conference in Birmingham on Monday, Ms Cross said the “confidence of the sector” was at stake.

“If Rosebank and Jackdaw are not permitted, you can pretty much guarantee that that is the end of the oil and gas sector,” she added.

“No company is obliged to invest in the UK.

“No company is obligated to keep producing in the UK.”

Ms Cross said energy firms would develop their businesses elsewhere in the world “if they can get better returns, better conditions, and have actually more liberty abroad”.

Mrs Badenoch on Sunday called for the country to have “clean, cheap abundant energy”, warning that the net zero by 2050 target was driving the country to increase its carbon emissions by importing fuels “from places where they drill in a very dirty fashion”.

She continued: “But Andy Burnham is too scared because he wants to win a by-election in Holborn and St Pancras and not scare off the Green Party voters, so he won’t do what even he knows is right, which is allow the drilling of oil and gas in our North Sea.”

Green Party leader Zack Polanski, who is standing in the Holborn and St Pancras by-election, has previously suggested rumours the Jackdaw project will be approved was “really outraging people” in the London constituency.

He said: “This is a constituency that cares even more than the average about tackling the climate crisis and the fact that this Prime Minister could be announcing new drilling for oil and gas in Jackdaw during this election, or delaying it until after the election if he doesn’t refuse to rule it out, that’s really outraging people.”

Mr Polanski is up against 14 other candidates at Thursday’s by-election, which was triggered when former prime minister Sir Keir Starmer left his seat in the House of Commons.

They include Labour’s Sagal Abdi-Wali and the Conservatives’ Ewan Cameron.