Here is what we know about the video, in which the then leader of the far-right Freedom Party (FPOe) Heinz-Christian Strache is seen appearing to offer public contracts in return for campaign help.
The revelations led to his resignation as party leader and vice chancellor on May 18.
What is in the video?
The video, more than six hours long, was recorded in a luxury villa on the Spanish holiday island of Ibiza in July 2017, just three months before Strache led the FPOe into Austria's last parliamentary elections.
In the extracts published so far, Strache is seen on a sofa, enjoying liberal amounts of alcohol and Red Bull, while speaking to a woman who remains off camera.
She is introduced to him as “Alyona Makarova”, purportedly the niece of Russian oligarch Igor Makarov — who has told the Russian edition of Forbes magazine that he has no nieces.
Strache's party colleague and trusted aide Johann Gudenus and Gudenus's wife are also present. “Makarova” is accompanied by a male associate, who also remains off camera.
Where did the video come from? –
Two German newspapers, the Sueddeutsche Zeitung (SZ) and Der Spiegel, published the extracts from the video on May 17 but said they could not reveal their sources and had no firm information on who organised the elaborate sting operation.
Since then Austrian media have reported that a Vienna-based lawyer, named as “M.”, organised the set-up and initiated contact with Gudenus. The lawyer's motivations are unclear, but according to the Die Presse daily he had previously offered to sell separate incriminating material on Strache to the FPOe's political rivals.
Germany's Bild daily late Friday said it believed “M” is Ramin Mirfakhrai, an Austrian lawyer of Iranian origin. Bild and Die Welt quoted Mirfakhrai's lawyer, Richard Soyer, as saying his client was involved in “a project with a civil society-related motive, in which paths of investigative journalism were pursued.”
This, Soyer added, created a “dynamic” narrative which resulted in Strache's resignation.
Mirfakhrai, who was not in Ibiza, is understood first to have met Gudenus two years ago to discuss a real estate purchase.
As to the associate who accompanies “Makarova” in the video, Austrian media named him on Thursday as Julian H., an Austrian with an investigative firm in Munich who helped the lawyer set up the sting.
While the Oesterreich tabloid reports that Julian H. and M. tried to sell the latest tape for millions of euros, SZ and Der Spiegel insist they did not pay for the material.
Rumours of the video's existence had been circulating for months, with the editor of the Austrian Falter weekly saying he had been aware of it since last year.
What does Strache say?
The most damaging part in the video is the discussion of how “Makarova” might take control of the Kronen Zeitung, Austria's largest-circulation tabloid, and use it to help the FPOe's campaign. In return, Strache says he would arrange for public construction tenders currently awarded to Austrian giant Strabag to be given to her instead.
Amid a welter of other embarrassing statements, Strache also appears to suggest a scheme through which political donations could avoid legal scrutiny by using an FPOe-linked foundation.
Who is 'Alyona Makarova'?
The FPOe says that she first made contact with Gudenus several months before the recording through the Vienna-based lawyer M. and Julian H. Gudenus says the woman wanted to buy some hunting grounds from him, apparently at five times actual value.
Julian H. then built up a rapport with Gudenus which led to the evening in Ibiza, as well as several subsequent meetings.
At one point in the video Strache seems to realise he's been set up — he says the woman's toenails are too dirty to belong to a rich Russian woman. But Gudenus reassures him it is not a trap.
How did Strache react?
While apologising for what he himself called “stupid” and “irresponsible” behaviour, Strache has quickly moved to portray himself as the victim of a shadowy conspiracy. On Tuesday, Strache posted a statement on Facebook vowing to prove his innocence and “unmask those behind this illegally made video”.