EU antitrust chief Margrethe Vestager said on Friday she would meet with the CEOs of Apple, Alphabet, Broadcom and Nvidia in the United States next week.

Antitrust experts expect Vestager to take a tougher stance on companies in mergers and competition investigations, a month after Vestager returned to the job a month after her failed bid to become president of the Luxembourg-based European Investment Bank.

Christina Holm Eiberg, an adviser to Vestager, said she would meet with Apple CEO Tim Cook, Alphabet CEO Sundar Pichai and its chief legal officer Kent Walker, Broadcom CEO Hock Tan and Nvidia CEO Jensen Huang in San Francisco and Palo Alto on Thursday and Friday.

She will also meet with OpenAI chief technology officer Mira Murati and chief strategy officer Jason Kwon. The conference will focus on European digital regulation and competition policy.

The meeting with Cook comes after the iPhone maker last year offered to give rivals access to its Tap-and-Pay mobile payments system for mobile wallets to resolve Vestager's investigation and avoid potentially hefty fines.

People familiar with the matter told Reuters last month that the European Commission was likely to seek feedback from competitors and customers this month but had not yet made a final decision.

Vestager will meet with Alphabet on January 11, the same day that an adviser to Europe's top court will make a non-binding recommendation on whether the judge should accept or reject the appeal of Alphabet's Google against a 2.42 billion euro (about $2.6 billion) antitrust fine imposed by the European Union for market abuse of its shopping service.