Michael Gove is at the centre of speculation suggesting he may be the source of the claims that the Queen backed Brexit in a row with former Deputy Prime Minister Nick Clegg.
The former education secretary is a close friend of Rupert Murdoch, owner of the Sun newspaper.
Gove is also going to head the Vote Leave campaign as chairman of its campaigning committee.
Gove's spokesman refutes the claims that he is the source of the story.
ITV News Political Editor Robert Peston reports:
Mystery shrouds the sources of reports claiming the Queen backed Brexit in a row with former Deputy Prime Minister Nick Clegg.
The Palace insists that the Queen is "politically neutral" over the EU referendum after the article was published, which claimed she backed Brexit in a row with former Deputy Prime Minister Nick Clegg.
The Sun newspaper cited a lunch at Windsor castle as the origins of the report.
The question being asked is who leaked what was or wasn't said at the Windsor lunch?
ITV News Royal Editor Tim Ewart reports:
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