The right-wing Swiss People's Party has elected Toni Brunner as its new leader at an extraordinary congress in Frauenfeld, in eastern Switzerland.
Brunner, a member of the Swiss parliament and well-known party activist who is close to its controversial figurehead, Christoph Blocher, takes over from Ueli Maurer, who has headed the party for 12 years and overseen its sharp rise in popularity.
Blocher, who was justice minister from 2003 to 2007, failed to regain his seat in government in 2007, despite being nominated by his party. In response the party withdrew its recognition of its two members whom parliament elected instead.
The People's Party then declared that it was going into opposition and would act to thwart all policies it disapproved of by calling popular votes.
Most speeches at the congress focussed on Switzerland's policy towards the European Union, one of the areas where the party has said it will combat the government.
Brunner came to public notice in 1995 when he became the youngest ever person to be elected to the Swiss parliament at the age of 21.
Blocher becomes one of the party's five vice presidents. The new party leadership elected Yves Bichsel as its secretary general.