Prime Minister Malcolm Turnbull has asked Qantas chief executive Alan Joyce to put extra flights on between north Queensland and Sydney for this weekend's NRL grand final, following complaints of exorbitant prices.

Mr Turnbull told Hit 103.1 Townsville on Thursday he was "concerned" about claims fares had skyrocketed since the Cowboys won their way into the decider.

Michael Morgan of the Cowboys is farewelled by fans at the Townsville Airport ahead of the NRL Grand Final at ANZ Stadium in Sydney this weekend. Credit:Michael Chambers

"I've actually just put the phone down to Alan Joyce," he said.

Mr Turnbull said Mr Joyce told him Qantas had already put on some more flights for this Sunday's game but encouraged him to go further.