Australian Broadcasting Corporation: Prime Minister John Howard has thrown his support behind federal Environment Minister Malcolm Turnbull, but has refused to say whether he believes Mr Turnbull leaked a story about urging federal Cabinet to ratify the Kyoto Protocol. Both Mr Howard and Mr Turnbull have refused to deny the reports that the Environment Minister put the case for ratification to Cabinet earlier this year. Newspaper reports today suggest that Mr Turnbull leaked the story to try and improve his …