Foreign aid spending could outstrip the defence budget within 15 years , according to an analysis published last night . Research conducted by the House of Commons Library found aid spending could eclipse defence by 2030/31 , assuming current spending changes continue under successive governments . According to the analysis , defence spending will be £27.1 billion by 2031 , but the aid budget will be £28.3 billion , the Daily Telegraph reported . Prime Minister David Cameron , who has dismissed concerns about the impact of cuts on the capacity of the British forces . In recent years , the Department for International Development has seen its budget increase sharply as ministers try to hit the target of spending 0.7 per cent of GDP on aid . Last week the Mail revealed that the Tory manifesto will not commit to keeping defence spending at the Nato target of 2 per cent of national income . Yesterday David Cameron dismissed concerns raised by the head of the US Army about the impact of cuts on the capacity of British forces , insisting it remained a 'very strong and capable partner ' for the Americans . In a sign of the pressure on the Prime Minister over the military budget , former Defence Secretary Liam Fox said he and fellow Tory MPs would find it 'hard to swallow ' if Mr Cameron allowed spending to fall below the 2 per cent Nato threshold while maintaining a pledge to spend 0.7 per cent of GDP on aid . Former defence secretary Liam Fox , pictured , has said he and fellow Tory MPs would find it 'hard to swallow ' if defence spending fell below the Nato threshold . Ministers are under increasing pressure from Tory MPs and senior military figures to commit Britain to meeting the Nato target after 2016 . With deep cuts to Whitehall budgets to continue after May 's general election , Chancellor George Osborne is reported to have warned privately that it may fall below that level . The most senior civil servant at the Ministry of Defence said that the department would 'clearly ' like the Nato target to be met - although he said that it would be for ministers in the next government to decide . Giving evidence to the Commons Public Accounts Committee , Jon Thompson , the permanent secretary at the MoD , said : 'Clearly , we would like 2 % of GDP but that 's for the next government to decide . ' He said that on current forecasts , GDP growth was expected to outstrip the growth in the defence budget , so that it would drop below 2 % at some point in the next parliament . He warned that further cuts in spending could ultimately affect the capability levels of the armed forces . 'It rather depends on how deep the cut is and how much further financial efficiency we can drive . If it were to be more than the level of financial efficiency we can drive , then yes , it will impact on capability , ' he said . Speaking at a campaign event in Colchester , the Prime Minister said the UK 's defence budget was the fifth largest in the world and second only to the US in the Nato alliance . He said : 'In terms of spending , the promise we have made is that the equipment budget , which is £160 billion over the next decade , that will grow by 1 % in real terms in each year of the next parliament . 'Also we have said we do n't want to see further reductions in our regular armed forces . So we have that commitment : second largest in Nato , fifth largest in the world . 'And as for working with the Americans , I know because I spend time with President Obama and others , how much they appreciate the fact that Britain is a very strong and capable partner and able to fight with them , when it 's in our national interest , anywhere in the world . '
According to analysis , defence spending by 2031 would be £ 27.1 billion . If spending changes continue , foreign aid budget would be £ 28.3billion . Department for Defence Development has seen sharp budget increase . Tory ministers will not commit to reducing defence spending at 50 % of GDP . prime Minister has expressed concerns about implementation of cuts on British forces .