In the only sworn testimony Lance Armstrong has ever made denying that he doped, in 2005, but broadcast on television for the first time last night, the seven-time Tour de France winner was adamant he never cheated and referenced how it would jeopardise the ''faith of all the cancer survivors around the world''.

Armstrong also denied, under oath in 2005, that he had ever received a blood transfusion.

His statements, obtained by ABC TV's Four Corners in Australia and aired in Australia last night, could lead to criminal charges of perjury and land him in prison.

Jeff Tillotson is the only lawyer who has extracted testimony from Armstrong under oath. The evidence he got in a case in 2005 was critical in investigations that ultimately led to the US Anti-Doping Agency's lifetime ban of the one-time hero.

Tillotson represented a Dallas-based insurer that Armstrong successfully pursued for millions of dollars worth of bonuses after he won successive Tours. The insurer initially refused to pay Armstrong some of the bonuses because it claimed the Tour was fixed. The basis of that claim was that it believed there was compelling evidence Armstrong had used drugs to win his fourth, fifth and sixth Tours.

Questioned by Tillotson under oath about using drugs, Armstrong passionately disputed the claim.

The sitting, which was filmed, began with Tillotson asking Armstrong: ''You understand that although we're in the conference room of your lawyers, you are giving testimony as if you are in a court of law? Do you understand that?''

Armstrong replied: ''Correct.''

Tillotson then said: ''And the penalties of perjury attach to this deposition just like they would to a court of law proceeding.''

Armstrong replied: ''Of course.''

In the sworn testimony, Armstrong acknowledged what would be at stake if he took performance-enhancing drugs.

Asked about sponsorship agreements, the cyclist replied: ''All of them. And the faith of all the cancer survivors around the world. So everything I do off the bike would go away too - and don't think for a second I don't understand that. It's not about money for me ... It's also about the faith that people have put in me over the years, so all of that would be erased.''

Tillotson told Four Corners: ''Whether it's a blessing or a curse, I remain the only lawyer to ... have actually taken sworn testimony from Lance Armstrong and to have had him deny, under oath, with the penalty of perjury that he used performance-enhancing drugs.''

The program tracked the genesis of Armstrong's doping back to former professional New Zealand cyclist Stephen Swart, who rode with the American on the Motorola team.

According to Swart, riders started complaining in 1995 that their European rivals were doping.

In a sworn statement, Swart recalled a conversation he had with Armstrong where the pair discussed the ''need'' to take EPO in order to be competitive. Armstrong has denied the conversation took place.

- The Age