London, England (CNN) -- British Prime Minister Gordon Brown is denying allegations of "abusive behavior" and "volcanic eruptions of foul temper" ahead of the publication of a new book by a top British political journalist. The claims come in a book by Andrew Rawnsley of the Observer newspaper, which will be released March 1. The newspaper began running excerpts on Sunday. "These malicious allegations are totally without foundation," Brown's official spokesman said in a statement Saturday. The spokesman is traditionally not quoted by name. The Observer claimed that Brown's behavior upset staff at his office, 10 Downing Street, so much so that the head of the civil service launched an investigation and "ordered" the prime minister "to change his behavior."
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Brown accused of "abusive behavior", "volcanic eruptions of foul temper"
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Journalist claims Brown's behavior was investigated by a top civil servant
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Brown "ordered to change his behavior," Andrew Rawnsley's book claims
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Brown spokesman: "Malicious allegations are totally without foundation"
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