The fine is the first punitive action against Facebook since the reports about Cambridge Analytica surfaced. Since the revelations, Facebook has grappled with regulatory scrutiny on both sides of the Atlantic. Its chief executive, Mark Zuckerberg, has appeared before Congress to answer questions about his company earlier this year and also met with European lawmakers.

In the United States, Facebook faces multiple inquiries by federal agencies. The Justice Department and the F.B.I. each recently broadened their inquiries into Cambridge Analytica by also focusing on Facebook. In addition, the Securities and Exchange Commission has started an investigation into Facebook’s statements on the matter, and the Federal Trade Commission is looking into whether the company violated a privacy agreement with the agency.

Facebook will have a chance to respond to the Information Commissioner Office’s initial report. A full version of the report, thought to be coming on Wednesday, is expected to detail the ways in which data gleaned from social media companies is increasingly being used to target voters by political campaigns.

Facebook did not answer a request for comment, and sent a written statement. In it, Facebook’s chief privacy officer, Erin Egan, said the Silicon Valley company was working with the British agency on its investigation and was reviewing the report.