BRUSSELS — The vexed question of Britain’s exit from the European Union, or Brexit, is all-consuming there, the stuff of daily leaks, denials, political proclamations and banner headlines in the nation’s newspapers, tabloid and otherwise.

Things are much calmer on the other side of the channel, where for the European Union, already looking beyond Britain to other challenges, Brexit is a second- or third-order issue.

“For Britain, it’s a question of head and heart, but for us it’s become a much smaller question,” Margrethe Vestager, the European Union’s commissioner for competition, said in an interview.

The European Union has huge issues bearing down: shoring up the euro; handling Greek debt; coping with the challenge to democratic values in countries like Poland and Hungary; and terrorism, security, migration and borders.