Britain must sort out its economy if it is to “carry weight in the world”, David Cameron will say later in a set-piece speech on foreign policy.
The prime minister will say he rejects any argument Britain is “in decline” internationally.
But he will say the quicker the UK gets its economy in order, the more credible its international impact will be.
There have been questions about whether defence cuts will mean the UK has to scale back future military operations.
BBC political editor Nick Robinson said predictions of the decline of the City of London and of the global dominance of the big Western powers, cuts to Britain’s military and questions about Mr Cameron’s stance on projecting British power abroad had fuelled the arguments that Britain was embarked on an inevitable path of decline.
Robert Kagan, former foreign affairs adviser to Senator John McCain, told ABC News on Sunday: “Britain has taken itself out as a major player in the international system, at least for a while, with the kind of cuts that they’ve made in their national security budget.”
And US Secretary of State Hillary Clinton, speaking before the UK’s wide-ranging defence review was published, was asked on the BBC whether the scale of defence spending cuts in countries like the UK worried Washington She said: “It does, and the reason it does is because I think we do have to have an alliance where there is a commitment to the common defence.”
In his first annual foreign affairs speech at the Lord Mayor’s banquet, Mr Cameron will say Britain’s foreign policy had to be one of “hard headed internationalism”, more commercial and strategic, and focused on “defending and advancing Britain’s national interest”.
“The faster we can get our domestic house in order, the more substantial and credible our international impact is going to be”
David CameronNick Robinson: Britain in decline?
According to pre-released extracts of the speech, Mr Cameron will say Britain’s “unique inventory of assets” – including its language, time zone, universities and the impact of the BBC and British Council – strengthened its “political weight in the world”.
Britain remains at the heart of powerful institutions like the G8, G20, Commonwealth and Nato, he will say, and is a “strong and active member” of the EU.
Its armed forces are respected internationally, it has the fourth largest military budget in the world and is the second largest contributor of troops in Afghanistan.
Mr Cameron will say other world leaders do not see Britain “shuffling apologetically off the world stage” but respected its “determination to get our economic house in order so we can remain masters of our nation’s destiny”.
“Economic weakness at home translates into political weakness abroad. Economic strength will restore our respect in the world and our national self confidence. So the faster we can get our domestic house in order, the more substantial and credible our international impact is going to be.”
He will add: “What I have seen in my first six months as prime minister is a Britain at the centre of all the big discussions. Producing the ideas. Consulted for our experience and respected for the skills we bring and our capacity to find solutions. So I reject the thesis of decline.”
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