Ryanair Holdings Plc is evaluating ordering bigger versions of Boeing Co.’s 737 single-aisle workhorse in a move aimed at boosting capacity on its longest routes, which could put additional pressure on rivals.

Europe’s largest discount airline is examining the business case for both the 737 Max 9 and Max 10, Chief Marketing Officer Kenny Jacobs said in an interview Wednesday. Dublin-based Ryanair has previously ordered only the 737-800 and its successor, the Max 8.

Buying bigger planes would allow Ryanair to increase capacity on its longest routes, such as Glasgow-Lanzarote or services to Israel, where the flying time limits aircraft utilization, Jacobs said at Bloomberg’s European headquarters in London. There’s no prospect of the carrier ordering the jets at next week’s Paris Air Show, he added, saying such a move would be premature.

“We’re a good customer of Boeing, and we will always talk to them about different models, including the Max 9 and 10,” Jacobs said. “A bigger aircraft wouldn’t change our operating model. It’s just that you can get more people on it and enhance the cost per unit. We’re not interested in having a varied fleet.”

Ryanair holds firm orders for 100 Max 200s—the high-density version of the Max 8—plus the same number of options. While a Max 9 or 10 purchase could in theory come from converting some of those existing commitments, the airline intends to firm up its options as stipulated when the time comes, so that buying bigger planes would almost certainly entail a wholly new deal, Jacobs said.

EasyJet Switch

The carrier would likely have a limited requirement for larger jets, the executive said, deploying them only at the extremities of its operations. Ryanair would be following low-cost rival EasyJet Plc in embracing bigger planes, with the U.K. company last month switching orders for 30 186-seat Airbus SE A320neo aircraft to the A321neo, which has 49 more seats.

EasyJet will look at converting more of its remaining 70 A320neo commitments to the bigger jet, Chief Executive Officer Carolyn McCall said in an interview, though the mid-size model will remain the core fleet, “bookended” by the A321 and smaller A319. The Luton, England-based carrier needs some larger jets to boost passenger numbers on busy routes at capacity-restricted airports, according to McCall, who spoke as it took delivery of its first Neo plane.

Boeing, seeking a model to match the biggest Airbus narrow-body, is expected to commit to building the Max 10 at the Paris expo, which starts Monday. The model will likely seat between 220 and 230 people in a single-class layout suitable for Ryanair, compared with 197 on the Max 200, Jacobs said.

Ryanair said last month that it plans to add at least 47 737s to its fleet by March 2018, a 12 percent expansion. It has 30 orders still outstanding for 737-800 planes. After retiring older models, the carrier will have a fleet of 595 jets by 2024, assuming it converts all order options.

Still, Ryanair is unlikely to be a customer for Boeing’s so-called middle-of-market plane, which is slated to feature two aisles in an oval-shaped cabin. “It’s probably not on our radar,” Jacobs said. “Single-aisle will always be what we do.”

Reuters reported Tuesday that Ryanair might place an order for the 737 Max 10, citing people with knowledge of the matter who didn’t identify.