Senior technical leaders will be invited to testify in the United States.

WASHINGTON (Reuters) – Leaders of big tech companies will be called to testify as part of an investigation into whether companies are misusing their huge market power, the chairman of the sub-bureau said on Tuesday. US Judiciary Committee.

Comments came a day after sources said the US executive branch was preparing for a similar investigation on Amazon.com, Apple, Facebook and Alphabet, on Google, putting together what could be a vast unprecedented investigation into some of the biggest companies in the world.

The Judiciary Committee of the House of Representatives opened on Monday its own investigation into competition in digital markets. Republicans and Democrats have expressed concern over the power exercised by many of the world's most valuable corporations.

Representative David Cicilline said, "It will be necessary for some of the leaders of the technology companies to participate in this discussion."

The Democrat added that he was preparing a list of witnesses and that he "expected that a number of them would testify before the committee or be interviewed in the framework of the investigation ".

House Republican leader Kevin McCarthy said Tuesday at a press conference that it was necessary to monitor large tech companies such as Google. It's just that people are looking at it, but added that he did not see how breaking businesses would help with privacy issues.

"Personally, I'm concerned about privacy," McCarthy said. Noting that a few companies have a lot of market control, he asked, "do we allow the market to work?"

Senator Mike Lee, a Republican, nonetheless said that the complexity of antitrust investigations suited federal agencies better than Congress.

Apple CEO Tim Cook said in an interview with CBS News on Tuesday that the company was a monopoly, claiming that the iPhone maker controlled a moderate share of the market but n & # 39; It was not too big and did not agree with the calls of some American politicians. that the company is dissociated.

"With size, I think control is right. I think we should be monitored, "he said. But, he added, "I do not think anyone is reasonable to come to the conclusion that Apple is a monopoly."

Cook's comments were released the same day that two app developers sued Apple for using the App Store, claiming that the company had taken an unfair commission on iPhone app sales.

The claims center on Apple's same practices highlighted in a lawsuit filed by consumers, arguing that Apple's practices had artificially inflated the price of software on the App Store.

The Federal Trade Commission and the US Department of Justice, which enforce antitrust laws in the United States, have split surveillance over the four companies, two people, Amazon and Facebook, told Reuters on Monday. Apple and Google the Ministry of Justice.

The FTC has already investigated the sharing by Facebook of data belonging to 87 million users with the British firm of British political counsel, now gone, Cambridge Analytica. Facebook said in April that it was expecting a fine of up to $ 5 billion from the regulator.

The owner of the Instagram and WhatsApp-era rivals has more than 1.5 billion daily users and exerts considerable influence in many countries. He has been criticized for allowing misleading publications and "false news" about his service.

In the interview granted to CBS, Cook also stated that "the false information was not under control" and, in response to a question on Facebook, had added, "I'm worried about any property that today introduces information into a stream. "Facebook did not immediately respond to a request. for comment.

Probes could have financial implications for businesses. Brokerage Cowen lowered its target price for Apple from $ 245 to $ 220 on Tuesday due to antitrust enforcement concerns. Equities rose 3.7% to $ 179.64 as the broader market also advanced.