Austria’s highest court has annulled the result of the presidential election narrowly lost by the far-right candidate of the Freedom Party.
The party had challenged the result, saying that postal votes had been improperly handled.
The Freedom Party candidate, Norbert Hofer, lost the election to the former leader of the Greens, Alexander Van der Bellen, by less than a percentage point.
The election will now be re-run.
Announcing the decision, Gerhard Holzinger, head of the Constitutional Court, said: “The challenge brought by Freedom Party leader Heinz-Christian Strache against the 22 May election… has been upheld.”
If elected, Mr Hofer will become the first far-right head of state of an EU country.
His party has based its election campaigns around concern over immigration and falling living standards for the less well-off.
Following the court’s order to re-run the vote, President Heinz Fischer will be replaced on a temporary basis by three parliamentary officials, including Mr Hofer.
The new election is expected to be held in September or October.