The decision, which will take effect from September 23, follows revelations earlier this week that Austrian authorities been investigating alleged questionable cash transactions tied to the AOC's failed bid to host the 2014 Winter Olympics in Salzburg.

Wallner said: "I am aware that personal changes are needed for restructuring.

"The chosen point in time guarantees a proper handing over which is important to the AOC and the sports in Austria."

Austria's Sports Minister Norbert Darabos had claimed earlier this week that it might be time for a "generation change" at the head of the Vienna-based AOC.

He said: "Leo Wallner's resignation is the right step in this situation that is so difficult for the Olympic movement.

"I've got the idea that finally a rethinking is taking place [within the AOC]."

The 73-year-old Wallner is Austria's longest-serving national Olympic committee President.

His announcement comes three weeks before an extraordinary general meeting to deal with the fallout of doping and financial scandals.

Wallner said: "I want to make clear that I am not going to let the AOC down.

"I will keep supporting them with all my strength in this difficult phase."

Wallner became the AOC's tenth President in 1990, taking over from Kurt Heller, and was re-elected for another four-year term last February.

Under his leadership, Austria has won a total of 105 medals in the Winter and Summer Olympics, including 27 gold.

Their best performance came at the Winter Games in Turin in 2006 when they finished third overall with a total of 23 medals, including nine gold.

But that was overshadowed by a major doping scandal that led to the International Olympic Committee (IOC) to fine the AOC £500,000 after six Austrian biathlon and cross-country skiers were banned from the Olympics for life.
 

The IOC made the ruling after an investigation into alleged blood doping at the Turin Games.

The athletes were found guilty of possession of doping equipment and collaboration after Italian police and dope busters raided the Austrian biathlon and cross-country skiing team headquarters in Turin.

Wallner, who had been general director of Casinos Austria for 40 years before resigning in 2007, has also been a member of the IOC since 1998.

The IOC said it had no comment.

The AOC had recently been hit by a financial scandal over murky money flows surrounding the failed bid to host the 2014 Games, which prompted General Secretary Heinz Jungwirth to step down earlier this year.

Wallner allegedly neglected to properly supervise the situation, in which lobbyist Erwin Roth (pictured) was paid more than $1.2 million (£1 million).

Wallner said: "These incidents made clear that the structures and control mechanisms didn't work properly.

"That's why we started a wide restructuring."

Jungwirth said Wallner's resignation was "the best" the President could do under the given circumstances.

"He [Wallner] has done a great job for 19 years and he doesn't deserve to be slammed by different people now.

"Next year is [the Winter Olympics in] Vancouver, it would be nice if the Committee was to get a strong leadership again soon."

The AOC's Executive Board decided on Monday to file official complaints against Jungwirth, who was held responsible for financial irregularities during his 25-year tenure.

Wallner declined to comment on the legal steps against Jungwirth.

He said: "The AOC and I want a detailed clarification of the facts and we don't want to influence the investigations in any way by giving a public statement.

"It's up to the courts now."

The Salzburg Public Prosecutor's office has already been investigating Jungwirth, Roth and two others since mid-February.

Salzburg lost the bid to host the 2014 Olympics to Sochi, Russia, two years ago.


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September 2009: Legal action taken in Austria over Salzburg 2014 Olympic bid
February 2009: Top Austrian official quits after financial scandal