– Luxembourg is a small country with big traffic jams.

So when Prime Minister Xavier Bettel was sworn in for a second term Wednesday, his governing coalition promised free mass transit for all, which would make the country the first to offer such a benefit.

Luxembourg is barely larger than a city-state, with a population of about 560,000. But more than 180,000 workers commute across the border from Belgium, France and Germany.

“It’s basically like a city which has suburbs abroad,” Olivier Klein, a researcher at the Luxembourg Institute of Socio-Economic Research, said Thursday.

Part of the problem is that Luxembourg already has the highest number of cars for its population in the European Union: 662 for 1,000 people, bringing it closest in the region to the United States, a world leader with more than 800 cars per 1,000 people.

The number of international commuters has doubled in the past two decades, rising more quickly than the country anticipated, Klein said. This has caused the kind of congestion familiar to those who commute into many big cities. Luxembourg’s highways are packed with cars, and overcrowded trains are often delayed.

Some cities in Europe and elsewhere already offer free mass transit at certain times and to people like retirees or the unemployed. Others are considering widening the circle to all users.

Free mass transit in Luxembourg will be available from the beginning of 2020, said Dany Frank, a spokeswoman for the Ministry of Mobility.