Some of Tony Abbott's most controversial speeches have been airbrushed from Coalition history since the election, including a 2009 speech in which he backed a carbon tax, and a 2004 speech in which he described abortion as ''a question of the mother's convenience''.

During Mr Abbott's 2009 carbon tax speech, in which he described himself as a ''climate change realist'', he poured doubt on climate change being man-made, saying: ''We can't conclusively say whether man-made carbon dioxide emissions are contributing to climate change.''

But he went on to say: ''If Australia is greatly to reduce its carbon emissions, the price of carbon-intensive products should rise … a new tax would be the intelligent sceptic's way to deal with minimising emissions.''

In opposition, the speeches were posted on Mr Abbott's website, tonyabbott.com.au. But since the September election, that website has redirected to liberal.org.au, which only archives material back to July 2010, the month before the previous election.