David Cameron has outlined his goals for reforming the UK’s membership of the EU, saying they will be difficult, but not impossible, to achieve.
He will formally set his demands out in a letter to the president of the European Council to be published later.
But he said he was confident of getting what he wanted, describing talks with EU partners as “mission possible”.
EU leave campaigners have described the process, which will be followed by an in/out referendum, as a “gimmick”.
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In a speech ahead of the letter’s publication, Mr Cameron said four objectives lie at the heart of the UK’s renegotiations:
- Protection of the single market for Britain and other non-euro countries
- Boosting competitiveness by setting a target for the reduction of the “burden” of red tape
- Exempting Britain from “ever-closer union” and bolstering national parliaments
- Restricting EU migrants’ access to in-work benefits such as tax credits
Mr Cameron hit back at claims by former Tory chancellor Lord Lawson that the four goals were “disappointingly unambitious”, saying they reflected what the British people wanted and would be “good for Britain and good for the European Union”.
“It is mission possible and it is going to take a lot of hard work to get there,” said the prime minister.
The toughest task he is likely to face is persuading other EU leaders to accept restrictions on in-work benefits for new arrivals to the UK, which Mr Cameron said was vital to cut “very high” and “unsustainable” levels of immigration.
He said: “I understand how difficult some of these welfare issues are for some member states, and I’m open to different ways of dealing with this issue.
“But we do need to secure arrangements that deliver on objectives set out in the Conservative manifesto to control migration from the European Union.”
Around 40% of EU migrants who have arrived in the UK over the last four years – about 224,000 people – are supported by the benefits system, new analysis from the Department for Work and Pensions suggests. Of these, around 66% – about 148,000 new arrivals – receive in-work benefits, such as tax credits.
Mr Cameron has said he wants the UK to stay in a reformed EU, but he has not ruled out leaving if he cannot secure the change he wants with the leaders of the 27 EU countries.
He ruled out a second referendum if Britain voted to leave, saying: “You the British people will decide. At that moment you will hold this country’s destiny in your hands. This is a huge decision for our country – perhaps the biggest we will make in our lifetimes. And it will be a final decision.”