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.

Despite Mr Abbott becoming opposition leader on December 1, 2009, all of his speeches and media statements before July 2010 have disappeared.

However, at least two recent transcripts have also been expunged from the public record. They include an interview on Sky with Chris Kenny in March, in which Mr Abbott vowed to lift foreign aid - a position he later reversed - and a speech to conservative think tank the Institute of Public Affairs this year.

In March, Mr Abbott was quizzed about whether he would heed the advice of former finance minister Nick Minchin, who said the Coalition could save billions by freezing growth in foreign aid.

Mr Abbott said: ''Well Chris, it's not our policy; our policy, and that of the [then Labor] government, is to lift foreign aid to 0.5 per cent of gross national [income] … It does remain our commitment … We are a generous people, we don't want to be niggardly in respect of our poorer neighbours.''

Five months later, the Coalition announced it would cut foreign-aid growth over the forward estimates, saving $4.5 billion.

The next month he gave a speech to the Institute of Public Affairs decrying a ''great Australian silence''.

''There is a new version of the great Australian silence, this time about the Western canon: the literature, the poetry, the music, the history and, above all, the faith without which our culture and our civilisation is unimaginable,'' Mr Abbott said.

It was posted on tonyabbott.com.au, but is not available on liberal.org.au. Intriguingly, nor is the government's direct action policy, the cornerstone of its climate-change policy, which has also disappeared from Environment Minister Greg Hunt's website.

A 2010 version of the policy remains available on Mr Hunt's website.

Since 1996, the National Library of Australia's Pandora project has archived websites and pages, including political material.

Since then it has collected content from more than 50 election campaigns, including every federal campaign, and has retained all of the pages formerly on tonyabbott.com.au.

A spokeswoman for Mr Abbott said: ''The Liberal Party website is being updated to provide a single website to access media releases, speeches and policy documents released prior to the election of the Coalition government.''

Tony Abbott's More Controversial Speeches Disappear