Delta Air Lines and distributor Travelport have struck a deal to sell Delta's "economy comfort" seats with more legroom for a fee through some travel agents.

The deal between Delta and Travelport, both based in Atlanta, marks a form of cooperation between an airline and one of its distributors amid some conflict between those industries. Disagreement between airlines and distributors, including the question of how travel agents might sell airlines' growing collection of extra services for additional fees, was the subject of a lawsuit pitting American Airlines against Travelport and online travel agency Orbitz last year.

Delta said the deal it announced Monday will allow travel agents who use Travelport's Galileo, Worldspan or Apollo global distribution systems to book economy comfort seats starting later this year.