Liz Truss accepted a £100,000 donation from the wife of a former BP executive.
Official records reveal the Prime Minister was handed cash for her leadership campaign by Fitriani Hay, the wife of James Hay, a former senior executive at the energy giant.
Entrepreneur Mr Hay is now chairman of Dubai-based JMH Group, which includes luxury goods and clothing brands and construction firms.
One firm, Fosroc, is a chemical firm which supplies construction products to the oil, gas and nuclear energy industry.
Mr Hay worked at BP for 27 years, before founding JMH Group in 2002 - and acquiring Fosroc, which was previously owned by BP.
In her first Prime Minister’s Questions after taking office, Ms Truss ruled out paying for the cap on energy bills with a windfall tax on energy producers - and promised massive investment in offshore oil and gas drilling.
"I want to see us use more of our energy supply, including more oil and gas from the North Sea and nuclear power," she said.
In total the new PM received more than £420,000 in donations to her campaign.
Rival Rishi Sunak raised more than £458,000 for his unsuccessful campaign.
Ms Truss’ fundraising also included £100,000 from Natasha Barnaba, the wife of Alessandro Barnaba, an investment banker and advisor to private healthcare firm Clinova.
There's no suggestion that any of the donations was accepted or declared improperly.
