Strache was Austria's vice chancellor until May, when he became embroiled in a scandal that brought down the country's government. A video showing him offering favors to a purported Russian investor prompted conservative Chancellor Sebastian Kurz to pull the plug on his coalition with the Freedom Party.
Strache had already announced earlier Tuesday that he was putting on ice his membership of the party he had led for 14 years and withdrawing from politics. The Freedom Party is investigating Strache for suspected breach of trust over the alleged billing of private expenses to his party, which contributed to its weak election performance on Sunday.
It finished third with around 16.2% of the vote, 10 points fewer than in Austria's 2017 election, as many supporters either switched to Kurz's center-right People's Party or stayed home. Kurz's People's Party finished first with 37.5% of the vote Sunday while the center-left Social Democrats saw their support fall to 21.2% but held on to second place, according to preliminary results. The environmentalist Greens staged a big comeback to get 13.8% of the vote.
Strache on Tuesday renewed his denial of any wrongdoing, but said he was getting out of politics to protect his family and prevent splits in the party. "I am announcing with a heavy heart that I am suspending my membership in the Freedom Party until further notice and until legal clarification of the accusations against me," he said.
"I am not only suspending my party membership but, as of today, also ceasing all political activity and not seeking any political function," he added in a statement to reporters in Vienna. Talk of an eventual comeback by Strache, 50, had swirled over recent months despite the video that prompted him to resign from the party leadership and Kurz to pull the plug on his coalition government in May. The footage, published by German news outlets Der Spiegel and Sueddeutsche Zeitung, showed Strache pandering to a woman claiming to be a Russian tycoon's niece at a boozy gathering in Ibiza two years ago, before he joined the government.
Strache portrayed himself as primarily the victim of a setup, although he renewed an apology for "my mistakes" on Tuesday. But the expense allegations, which became public shortly before the election, cost him sympathy from supporters.
Strache said he was "a bit disappointed" that talks he had sought with the new Freedom Party leadership under Norbert Hofer hadn't taken place.