Germany’s foreign ministry has hit back at U.S. Secretary of State Marco Rubio after he criticized the decision to classify the Alternative for Germany party as a “right-wing extremist” organization.

Four candidates are bidding to be Germany’s next leader in Sunday’s election.

Projections show that Germany’s unpopular governing parties sank to feeble results and the far-right Alternative for Germany made gains in Sunday’s vote for the European Parliament, while the mainstream conservative opposition was the country’s strongest political force by a distance.