Lizz Truss enters no. 10 Downing Street during high-stakes wars; both within her party, and on the Eastern borders of Europe. However, her first battle as prime minister will be tackling the energy bill crisis. This daunting task is made ever more difficult by Truss’s commitment to a low tax economy.

The cost of a cap on energy bills depends largely on its form. A targeted plan to help the most vulnerable households, such as £650 for those on means-tested benefits, would be cheaper. However, it would be difficult to implement quickly and effectively and it would leave families just above the threshold in a precarious position. A blanket tax break would benefit richer households with disposable income, and would cost substantially more.

Furthermore, the cost of the energy cap will likely be increased by factors outside of Truss’s control. Putin has taken a stance against western sanctions by extending the closure of Nord Stream 1. This will increase the price of gas as well as the cost of Truss’s relief plan. As well as this, a relief package of this scale will increase public spending in a demand charged inflation spike, spurring a further rise in interest rates.

With a public debt to GDP ratio of 96%, investor confidence in the UK is low. Couple this with extensive high-interest rate borrowing, Truss will need to provide extensive assurances on payment plans in order to attract foreign investment. However, as of yet all she has done is ensure that taxes will be slashed.

If Truss decides to increase taxes, either approach will be politically difficult. A general tax would be a rejection of her low-tax promise, which could be seen as a return to the laissez-faire approach to policy integrity endured during the Johnson administration. However, a long-term repayment of tax breaks could cut vulnerable households adrift, which would be detrimental to the economy.

With a worryingly high cap on costs, and no real plan to raise funds for repayments, investor confidence is at a worryingly low level. On Monday, Shreyas Gopal of Deutsche Bank claimed the UK could be on a “balance of payments crisis”. Although unlikely in a G7 economy, the risk of a balance of payments crisis is no longer negligible. Therefore, in order to attract foreign investment and fund her relief package, Truss will have to depreciate the value of Sterling substantially, with Deutsche Bank claiming that a devaluation of 30% may be required to attract foreign investment into Britain.