Former foreign secretary Lord Owen has stressed the need for a referendum to be held on Britain's membership of the European Union.
Speaking on BBC Radio 4's Today programme, he said: "We'll be far stronger in Europe if it's seen we speak with one voice."
Lord Owen, who has written a book on the issue, Europe Restructured?, said he wants a referendum on whether the UK should be part of the single market in a wider European community and on whether the UK should remain in the European Union - keeping open the option of joining the more integrated eurozone.
He said: "I think the country feels cheated that they didn't have the promised referendum... The European Union is changing and the British Government needs to lift its voice."
He said the move would help protect British industry and added: "We need a single market without a single government."
The referendum would be handled in a similar way to the Scottish referendum, Lord Owen suggested, adding that it was "time to sit down as adults" to debate the matter.
Lord Owen, who gave a copy of the e-book to fellow Today programme guest Chancellor George Osborne this morning, also recommended inviting Turkey to join the single market. He said: "It's long been a disgrace that we've not accepted Turkey."
A product description of his book on Amazon says it "considers how Britain's place in the EU affects her other global foreign and defence relationships, in particular with the United States".
It adds: "All this leads David Owen to the conclusion that urgently in 2013, or more likely in 2015-2016, a referendum will have to be held in the UK."
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