Political leaders have shunned the Alternative for Germany. But on his social media platform X, Mr. Musk is pitching the party as mainstream.

Elon Musk praised the co-leader of the German party Alternative for Germany (AfD) as “very reasonable” on Thursday, urging Germans to vote for the far-right party in what is the latest high-profile sign of the tech billionaire’s involvement in European politics.

Tech billionaire Elon Musk live-streamed a chat with a leader of Germany's far-right party on Thursday, using the power of his social media platform, X, to amplify its message ahead of an upcoming national election and raising concerns across Europe about potential meddling by the world's richest man.