Fitriani Hay, the wife of James Hay, donated £100,000 to Mrs Truss. It came as the new prime minister unveiled her plan to help families struggling with their energy bills. Mrs Truss said she would freeze the £2,500 bills, which would be paid for by additional government borrowing. He refused to extend the windfall tax on the big profits of oil and gas giants. James Hay joined BP as an engineer in the 1970s and spent nearly three decades working for the multinational, later becoming a senior executive. He is now the chairman of the Dubai-based JMH Group, a private family business active in the luxury goods market. Mr Hay married his wife Fitriani in 1996 and they have two daughters. According to The Sunday Times Rich List he is worth £325 million. The donation may cause concern given Ms Truss’s refusal to further tax oil and gas companies to help people with soaring bills, fueled by Russia’s war in Ukraine. Rishi Sunak, whom Ms Truss defeated in the race to replace Boris Johnson, introduced the initial levy and said he was open to extending it if he became prime minister. Opposition parties have also called for an additional windfall tax, a policy that is widely popular with voters and has been introduced in many countries across Europe. Ms Truss said extending the levy would deter investment – something Mr Sunak said before later moving into politics. Rishi Sunak and Liz Truss during the leadership competition (PA wire) In the House of Commons on Thursday, Ms Truss confirmed that energy bills for the average household would be frozen at no more than £2,500. He also confirmed that businesses would be spared crippling increases. Her two-year plan, paid for by borrowing tens of billions of pounds, will save the typical household around £1,000 from October and protect ratepayers from further expected rises in the coming months. Prime Minister Liz Truss presented her energy plan to MPs (House of Commons/PA) (PA wire) For businesses and other non-residential users, such as schools and hospitals, not covered by the existing price cap, a six-month program will provide equivalent support. Ms Truss told MPs: “This is the time to be bold. We are facing a global energy crisis and there are no costless options.” Downing Street has refused to fund the scheme, which was previously estimated to cost up to £150 billion. The prime minister’s official spokesman would only say the price would be “tens of billions”.