Whoever becomes prime minister this week – most likely Rishi Sunak or Boris Johnson – will face the most daunting in-tray of anyone in No 10 for decades. These are the pressing issues they will have to make decisions on in the coming months ahead. Fiscal plan Sunak has declared that fixing the economy is his priority. The Treasury is facing a £40bn black hole and the interim chancellor, Jeremy Hunt, is working on a plan to make the sums add up by 31 October but this will mean swingeing cuts. A new prime minister will have to make a call on how big the cuts will be – or whether to opt for tax rises instead. Benefits One of the biggest decisions on this front is whether to uprate benefits in line with inflation. Most of the centrists within the party believe this is essential and that any attempt to swerve this would not get through parliament. Public sector pay and strikes Public sector pay is similarly problematic when it comes to inflation. Nurses, healthcare staff, ambulance drivers, teachers, train drivers, civil servants, university lecturers and many others are considering strikes this winter in the face of real-terms pay cuts. The government may have to reconsider their settlements if it wants to avoid large-scale disruption to society. NHS winter crisis and waiting lists The NHS is in a dire situation heading into winter with the threat of a “twin” Covid and flu season, demoralised staff and long waits for operations, GP appointments, A&E services and ambulances. A new prime minister will have to take a decision on whether NHS spending should be ringfenced from cuts, as well as how to deal with the existing pressure on services. Energy The government has provided energy bill support until April but now will not say how much if any subsidy it will give people after that point. There is also the threat of winter blackouts if gas supply remains tight across Europe as a result of Russia’s war in Ukraine. One of the first actions of a prime minister could be to announce a major energy-saving campaign – a move resisted by Liz Truss previously. The Northern Ireland protocol The protocol issue remains unresolved, though Liz Truss made progress towards new talks. Although a different tone has been set, Eurosceptic Northern Ireland minister Steve Baker warned on Sunday that his faction would not hesitate to bring the next government down if they reneged on promises to protect free trade within the United Kingdom. Pensions triple lock The government committed to maintaining the triple lock – raising pensions by the highest of inflation, wages or 2.5% – at the last election. However, if cuts need to be made, a new prime minister could look at phasing this out, but that would make many Tory MPs dependent on the votes of older people deeply unhappy. Defence spending Defence spending had been due to rise to 3% of GDP by 2030, but scrapping this pledge is one option under consideration as the government seeks to balance the books. Ben Wallace, the defence secretary, has made clear he is committed to the policy. Planning Liz Truss had wanted to undertake broad planning reforms as part of an overhaul of supply-side measures to boost growth. Her government was looking at loosening planning restrictions for large infrastructure and in investment zones but also more widely. This would be very controversial among Tory MPs. Immigration A row over immigration was raging in the hours before Truss’s departure as prime minister. She had wanted to relax restrictions to boost growth, but this was being resisted in the Home Office. A pro-growth prime minister is likely to want to loosen curbs to try to improve the economy. Foreign aid Foreign aid spending is due to return to 0.7% of national income but a prime minister intent on cuts could delay that date. That would infuriate the one nation wing of the party, many of whom have supported Sunak over Johnson. Inquiry into Boris Johnson’s conduct Johnson as prime minister would face a huge headache over the impending parliamentary inquiry of the privileges committee over whether he misled the House of Commons. Sunak is also likely to find it problematic given the attention it will take up, though less so than Johnson. The inquiry is due within weeks to sit up to four hours a day for three to four days a week hearing evidence about the Partygate scandal – a spectacle that is likely to dominate the headlines and reignite anger.