Disagreement on timing for a fleet roll-out, among other issues, led OnAir to terminate its agreement to provide on-board to fit mobile phone service across budget carrier Ryanair's fleet.
Ryanair began a trial of the service in February last year, with a view to equipping all its Boeing 737-800s, and OnAir had fitted its system to 50 aircraft over the test period.
However, OnAir says the two companies had failed to reach a "mutual agreement on the process and timing" leading to full deployment.
"It's disappointing that OnAir and Ryanair couldn't reach agreement on the details of a roll-out to their entire fleet, but our experience was extremely positive and we wish Ryanair every success in the future," says OnAir chief Benoit Debains.
Neither side is commenting further on the situation.
Six airlines currently operate the OnAir system and a further six carriers are due to launch the service during 2010.
OnAir says it has 23 signed agreements with carriers and will "very shortly" disclose new agreements with other carriers for both short-haul and long-haul aircraft.