Germany's Angela Merkel began the tough task of trying to build a coalition government on Monday after securing a fourth term as chancellor in an election which saw her support slide and the far right making significant gains.
Damaged by her decision two years ago to allow one million migrants into Germany, Ms Merkel's conservative bloc secured 33 per cent of the vote, losing 8.5 points -- its lowest level since 1949.
Her coalition partners, the centre-left Social Democrats, also slumped and said they would go into opposition.
Martin Schulz, leader of the Social Democrats that have governed with Ms Merkel since 2013, said his party had no choice but to go into opposition after dropping to a post-war low of 20.5 per cent.
"We have understood our task -- to be a strong opposition in this country and to defend democracy against those who question it and attack it," Mr Schulz told party members.
Voters flocked to the anti-immigration Alternative for Germany (AfD), the first far-right party to enter the German parliament in more than half a century.
However, the AfD hardly had time to savour its third-place showing before it fell into internal bickering.
Co-leader Frauke Petry, one of the party's most prominent faces, said she would not sit in parliament with AfD members.
It was not immediately clear why she was making such a move.
Leading AfD candidate, Alexander Gauland, gave a foretaste of the hostile new tone expected in parliament, saying it would "hound" Ms Merkel and "get our country and our people back".
After the SPD ruled out another "grand coalition", Ms Merkel's only other choice is to pursue a three-way partnership between her conservatives, the FDP and the Greens.
The Greens say the next government should be pro-Europe, adding coalition talks will be complicated, but they will approach them in a responsible way.