TOULOUSE, France — Airbus is accusing Boeing of making misleading claims about its planes’ performance, and it ridiculed its competitor with an advertising campaign showing a Boeing jet nose grotesquely elongated to resemble Pinocchio’s.

The ad, which appears this week in trade publications including Aviation Week and Flight, asserts that Boeing is “stretching the truth” in its own campaign to promote its aircraft. Boeing said it stands by its performance claims.

“They crossed a line when they started running specific numbers,” Airbus’ John Leahy said. “They’ve blatantly misrepresented the facts.”

The bickering highlights the stakes in the $70 billion global civil aviation industry as the companies fight to trump each other in orders.

Airbus is set to lose its delivery lead this year for the first time in almost a decade, after Boeing overcame production delays and began shipping its new 787 Dreamliner to customers.

Airbus and Boeing are drawing comparisons with each other’s narrow-body aircraft, the industry’s workhorses, and their four-engine A380 and 747-8 jumbo jets.

Leahy said Airbus was driven to act only after Boeing ran ads with specific claims about the alleged superiority of its 737 Max over the A320Neo, and its 747-8 over Airbus’s A380.

The 737 Max ad claims the plane’s costs on a per-seat basis are 8 percent less than an A320neo’s. Airbus wrote to Boeing’s general counsel complaining that the numbers are “wildly out of line,” and placed ads targeting airlines only after Boeing did not respond, Leahy said.

“We received the letter and responded weeks ago that we are fully confident in the accuracy of the statements made in our advertisements,” Boeing spokesman Marc Birtel said in an email.

The two planemakers combined have delivered more than 12,000 narrow-body planes since Boeing 737s reached their first customers in 1967. In its ad, Airbus said it is now dominant in the market for very large aircraft with its A380 double-decker, a niche where Boeing has struggled to match the popularity of earlier versions of its iconic 747 jumbo.

Airbus and Boeing have sparred in public before. Some 15 years ago, Airbus took out ads touting the now-canceled four-engine A340 as safer than a twin-engine Boeing model.

Boeing took umbrage that its rival had breached an unwritten understanding not to use safety issues to market its planes.