Rishi Sunak has pledged to deliver on the 2019 Conservative Party manifesto which saw Boris Johnson win a landslide general election victory. But question marks hang over a number of key commitments ahead of next week’s autumn statement.It comes as the Prime Minister and the Chancellor look to plug a £60 billion black hole in the public finances.Jeremy Hunt will unveil the tax rises and spending cuts in the highly-anticipated autumn budget on Thursday next week.However Mr Sunak could face a sizeable rebellion from his own MPs over some reported measures.Here Express.co.uk looks at the areas where the PM could ditch manifesto commitments: Rishi Sunak has pledged to deliver on the 2019 Tory manifesto (Image: GETTY)The Prime Minister is reportedly looking at raising the top raise of income tax.Upping the 45 percent rate or lowering the £150,000 threshold are being discussed, the Telegraph reports.Increasing the rate would break an explicit promise in the 2019 Conservative manifesto, although tweaking with the threshold could be a way around the pledge.The move would be a dramatic departure from Mr Sunak’s predecessor Liz Truss’s plan to scrap the top rate altogether which she later U-turned on.National InsuranceMr Sunak is also said to be considering increasing the National Insurance rate paid by employers by 1.25 percent.It comes after Ms Truss reversed the 1.25 percent rise for employees, employers and the self-employed announced by Mr Sunak when he was Chancellor.The move would break the 2019 Tory manifesto which stated: ‘We will not raise the rate of income tax, VAT or National Insurance.’The triple lock – a manifesto pledge – was thrown into doubt when Mr Sunak entered No 10 as he refused to commit to the policy, which sees state pension payments uprated by the highest out of 2.5 percent, wages and inflation.Mr Sunak and Mr Hunt are mulling whether to raise state pensions, as well as benefits, in line with soaring inflation.The Daily Express launched a campaign to save the triple lock, with almost 300,000 people signing our petition.The policy now looks likely to go ahead next April, with the Work and Pensions Secretary yesterday insisting OAPS will be kept to the “forefront” as difficult spending decisions are taken. Jeremy Hunt will unveil the tax rises and spending cuts in the autumn budget on November 17 (Image: GETTY)The 2019 Tory manifesto made a number of pledges on defence spending, but Defence Secretary Ben Wallace last week said he lives “in the real world” as he acknowledged the need for the new PM to balance the books.The manifesto stated: “We will continue to exceed the Nato target of spending 2 percent of GDP on defence and increase the budget by at least 0.5 percent above inflation every year of the new Parliament.”Mr Johnson previously agreed to increase the defence budget to 2.5 percent of national income by the end of the decade – compared to the Nato minimum of 2 percent – a commitment Ms Truss subsequently lifted to percent.During the summer Tory leadership campaign, Mr Sunak branded a three percent of GDP target ‘arbitrary’.Other tax rises understood to be on the table include increasing the headline rate of capital gains tax which is paid on the sale of assets such as shares and second properties.There are also reports of a stealth raid by freezing inheritance tax thresholds, while a dividend tax hike is said to be under consideration.But the 2019 Tory manifesto stated: “We not only want to freeze taxes, but to cut them too.”