DESCRIBING it as "a big execution", former federal treasurer Peter Costello has effectively endorsed the leadership coup against Tony Abbott.
Mr Costello said it was "most certainly" the correct decision for the Liberal Party to install Malcolm Turnbull as Prime Minister.
Based on opinion polls since Mr Turnbull replaced Mr Abbott, Mr Costello said it appeared to have been the right decision.
He said that for the Abbott government "a significant loss was on the cards" and now "a significant victory" at next year's election was now a possibility.
Mr Costello made his first public comments about the change of Liberal leadership as part of a Four Corners program to air tonight.
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