The pilot due to fly a 'Moyes Out' banner over Old Trafford on Saturday said he would also carry a banner in support of the manager if he was asked to.
Speaking to ITV News sports correspondent Ian Payne, Chris Mustow said his company Air Ads had declined some "colourful" requests for messages in the past.
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British soldiers will join troops from some 30 countries who work in the country.
The demand comes after the Prime Minister urged a "grown up" relationship between her government and the devolved administrations.
The rapper failed to make it to London in time as he had problems with his passport.