For a ruling that has been looming for more than two years, the timing of the European Commission’s €13bn tax penalty could not have come at a worse moment for Apple.

Not only does it place Apple at the top of a growing list of US companies that are charged with massive tax avoidance at a time when discontent about globalisation generally is at a new high, it marks the beginning of a bruising legal fight that could distract its leaders for years to come.

In the near term, the commission’s finding that the world’s most valuable company benefited from 25 years of illegal state aid from Ireland comes just a week before the launch of its latest iPhone. Every such launch is hailed as crucial for Apple’s future — the iPhone accounts for two-thirds of its revenues — but this will be the first to come when sales of its flagship product are in decline, putting extra pressure on Tim Cook, chief executive, to deliver.