The globe's biggest telecommunications trade show is held every year in Barcelona, Spain, intended to celebrate Europe's pivotal role in the genesis of the mobile industry.

This year, the top speakers are two Americans who symbolize pressing threats for the region's carriers.

As more than 85,000 attendees gather for the four-day Mobile World Congress - among them Facebook Inc Chief Executive Mark Zuckerberg and US Federal Communications Commission Chairman Tom Wheeler, who will be giving keynote addresses - executives are fretting over the growing digital divide between Europe and the US.