BERLIN - German authorities have been pushing back against criticism from the US side concerning Germany's decision to classify the far-right Alternative for Germany (AfD) party as a confirmed right-wing extremist organization.

The decision was made by the Federal Office for the Protection of the Constitution (BfV) on Friday, stating that the AfD's prevailing "ethnic-based concept of the people" is incompatible with Germany's liberal democratic basic order.

In a post on the social media platform X, US Secretary of State Marco Rubio said that "the popular AfD," which took second place in a recent federal election, should not be considered extremist.

The German Foreign Office defended the country's move responding directly via its official account.

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"This is democracy," the office said in the reply, adding that this decision is the result of a thorough and independent investigation to protect the country's constitution and the rule of law.

"We have learnt from our history that rightwing extremism needs to be stopped," said Germany's foreign office.

US Vice-President JD Vance also posted on X in a response, noting that "the AfD is the most popular party in Germany, and by far the most representative of East Germany."

"Now the bureaucrats try to destroy it," said Vance. "The West tore down the Berlin Wall together. And it has been rebuilt...."

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The dispute comes as Germany prepares for a new government to take office next week.

Alexander Dobrindt, nominated by the Christian Social Union (CSU) to become Germany's new federal interior minister, dismissed Vance's critique as "absurd" in comments made to German public broadcaster ZDF.

The incoming minister added that he expects it will be made clear to the Americans in future discussions that the AfD is fundamentally extremist.

In response to the BfV's decision, AfD leaders Alice Weidel and Tino Chrupalla called it a heavy blow against democracy.

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The party's leaders said the AfD will continue to defend itself legally against these democracy-endangering defamations.