Both Aurigny and Blue Islands have opposed the new Flybe application for a licence submitted to the Guernsey department of Commerce.
Flybe say that the application has ‘rattled’ both rival carriers.
Guernsey is the last place in Europe that forces airlines to have to apply for a licence to operate any routes to and from the island.
Flybe have failed on a number of previous occasions to persuade the Guernsey air licensing authorities to allow it to fly inter-island.
Guernsey States bought Aurigny in 2001 after British Airways gave up the Gatwick route.
BA agreed to sell the take-off and landing slots at Gatwick to the Guernsey authorities, who in turn bought Aurigny to ensure continued links to London.