Headteacher Anthony Seldon has been caught up in political speculation about Tony Blair's Cabinet reshuffle.
Dr Seldon, in charge of Brighton College, is an authoritative political biographer and is updating Mr Blair's biography with an account of the Prime Minister's first 100 days in office in his third term.
In it he says Mr Blair is unimpressed with Home Secretary Charles Clarke and finds him "too tame".
This has led to speculation Mr Clarke's days are numbered and there could be a reshuffle before the party conference in Brighton with the Home Secretary sacked and young Blairites promoted.
But Dr Seldon told The Argus he did not think Mr Blair would immediately sack the Home Secretary on his return from his family holiday in Barbados.
He said: "There are a number of differences but I think they will try to work them out.
"It is true that I have written the Prime Minister has never been all that impressed with Clarke. He finds him too tame."
Dr Seldon says he believes Mr Blair is stronger than ever and his popularity as Labour leader within the party and the country will lead to a strong performance at the conference in Brighton at the end of next month.
Dr Seldon, who is about to start his last term as head of Brighton College before joining Wellington College, Berkshire, said: "Mr Blair was weak earlier this year and at points during the election campaign but he is now back to his strongest."
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