U.S. social network Facebook is set to be penalized by EU antitrust regulators for allegedly providing misleading data related to its WhatsApp acquisition three years ago, a person familiar with the matter said on Wednesday.

The move by the European Commission will come after a six-month investigation and is expected to be a stiff warning to other companies facing similar issues.

The EU executive and Facebook declined to comment.

During regulatory scrutiny of the WhatsApp deal in 2014, Facebook told the EU competition enforcer it was unable reliably to match the two companies' user accounts.

Facebook reports 1.2 billion daily users Alongside its latest earnings report, Facebook has revealed updated user data about the social network and the firm's other services, with figures that continue to climb to dizzying new heights. 

The Commission subsequently found that this was technically possible at the time.

Regulators met this week on the case and a decision could come either this week or next, the person said.

The Commission can fine a company as much as 1 percent of its global turnover, which in Facebook's case could reach $276 million based on its 2016 revenue.

European Competition Commissioner Margrethe Vestager in March told a news conference that a small handful of companies may have provided misleading information when they sought approval for their mergers.

The EU sanction will come on the heels of a 150,000-euro fine handed down by a French data watchdog to Facebook on Tuesday for failing to prevent its users' data being accessed by advertisers.

Italian antitrust authorities levied a 3-million-euro fine on WhatsApp last week for allegedly obliging users to agree to share their personal data with Facebook.