Frontier Airlines yesterday said it reached a “mutual agreement” with Republic Airways to end their code-share agreement and gradually remove all 12 of the Indianapolis-based regional airline’s Embraer E170s from the Frontier network by mid-June. The announcement came less than two weeks after Frontier filed for bankruptcy and embarked on a reorganization that will see it end service to at least five markets served by Republic and suspend plans to enter Missoula, Mont., on May 16.

Republic had planned to field at least 17 of the 76-seat jets within the Frontier system within two years. Although the separation appears amicable, Republic said it plans to file a $260 million damages claim with the bankruptcy court overseeing Frontier’s case. Republic said the agreement with Frontier generated roughly $6 million a month. It said it plans to seek another partner with which to place the airplanes, including the five still due for delivery from Embraer.

“We have enjoyed our partnership with Frontier and have a lot of respect for their people,” said Republic CEO Bryan Bedford. “It’s unfortunate that despite their many efforts to reorganize their business outside Chapter 11, factors beyond their control conspired to force a deeper reorganization. We wish them success in their continuing efforts to combat persistently high oil prices.”