Senator Cormann has been described by some Liberal colleagues as the "commander-in-chief" of Peter Dutton's insurrection campaign against ousted prime minister Malcolm Turnbull.

In a new book written by political journalist Niki Savva, some colleagues have claimed he was "heavily involved" in the plot to install Mr Dutton.

They argue his decision to withdraw support from Mr Turnbull was "deliberately staged and timed" to help his leadership rival.

Former foreign minister Julie Bishop labelled him "the ultimate seducer and betrayer" of Mr Turnbull.

"It was a difficult week," Senator Cormann told ABC Radio on Monday, when asked if he was a "political Judas".

"I made decisions based on what I felt was right, on the basis of what I thought was necessary, and in the best interests of the country and the government and the Liberal Party."

Senator Cormann, who declined to be interviewed for the book, argued the claims aired against him were "mostly inaccurate or one-sided".

Australian Associated Press