ITV News Political Correspondent Carl Dinnen has tweeted:
Asked if PM knew of earlier complaint against Rock, PMOS said 'The PM is always kept informed of relevant staffing issues.'
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The Democratic presidential candidate may also have shown his cards on his choice of running mate.
The US president also shared a post on Twitter accusing Dr Anthony Fauci of misleading the public over hydroxychloroquine.
Fears over an impending second wave of coronavirus dominates Wednesday’s front pages.