WARSAW, Poland — Tech billionaire Elon Musk livestreamed his chat with a leader of Germany’s far-right party on Thursday, using the power of his social media platform, X, to amplify the party’s message ahead of an upcoming national election — and raising concerns across Europe about the world’s richest man trying to influence foreign politics.

Musk, who worked last year to help re-elect Donald Trump in the United States, told Alice Weidel, a co-leader of the Alternative for Germany party and its candidate for chancellor, that he was “strongly recommending that people vote for AfD,” using the party’s acronym. The audience for the livestream peaked at more than 200,000 X accounts.