WestJet's expansion into Europe takes off this weekend with the carrier’s inaugural flight across the Atlantic Ocean on Sunday.

The Calgary-based airline will fly between St. John's, Nfld., and Dublin, Ireland.

Already, the company says 80 per cent of the seats are sold.

"It's the most successful service from the point of announcement to the point of launch in WestJet's history. So things obviously look promising for future expansion," said spokesperson Robert Palmer.

"It's a mixture of people buying the tickets, but for the most part there are a lot of people from the Maritimes."

The flights will be offered until the end of October.

Europe expansion plans

With its current fleet of aircraft, WestJet could fly from St. John's or Halifax to cities in England, France and Scotland.

But the company would likely invest in wide-body aircraft, such as the 787 Dreamliner, to increase efficiency of any future international flights.

"I would say in the wide-body world, we're going to start carefully with a small number of aircraft and see how it goes," CEO Gregg Saretsky told reporters in May.

"It's early days, obviously. There's lots of work that needs to be done."

The upcoming flights to Ireland are a way for the company to feel out the European market and then decide what step to take next, Palmer said.

"One of our goals is to be a top international airline in every sense of the word. So that's something we look for on our horizon."