Alternative for Germany appears to be headed for the strongest showing by a far-right party since World War II in Sunday’s national election and is fielding its first candidate to lead the country.

Polls are open across Germany as the world’s third largest economy chooses a new leader to guide it through an era of febrile immigration debates and souring relations with Washington.

This election in Germany will reveal if one of Europe's major powers gets a stable government, the direction its flailing economy could take, and how Berlin will deal with a Europe in turmoil and an unpredictable US.