The Sun said that a "highly reliable source," which it did not name, who was present at a lunch at Windsor Castle at which Clegg was a guest, said that the Queen "let rip" at the well-known Europhile politician over Britain's continental neighbors, telling him that she though the political and economic bloc was "heading in the wrong direction."
The senior source quoted by the paper said: "People who heard their conversation were left in no doubt at all about the Queen's views on European integration…The EU is clearly something Her Majesty feels passionately about."
Buckingham Palace said on Wednesday morning that it would not comment on "spurious" claims. The palace insisted the Queen is "politically neutral" over the EU referendum and launched a complaint with Britain's press watchdog, Ipso, later in the day.
Clegg, meanwhile, called the story "nonsense" using the social media site Twitter.
The claim by the newspaper comes ahead of a referendum on the matter in June, which has sparked a heated debate within the country.
Whether fact or fiction, the comments could be a boost to the "leave" campaign which has already attracted a number of high-profile politicians from the ruling Conservative party causing a split with leader and Prime Minister David Cameron who is campaigning for Britain to stay in a reformed EU.
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