Alderney States is "disappointed" Guernsey's States have hiked air-fares without consultation.
Guernsey is cutting subsidy on Alderney flights by half a million pound in January 2025 - to £1.5M.
This is expected to increase passengers prices further - on top of yesterday's £5 increase.
Guernsey's States agreed in 2022 to reduce financial support, once Alderney's airport runway was extended.
Alderney's Policy & Finance Chairman Nigel Vooght says while the airport project is paused indefinitely, the withdrawal of half a million pounds is 'out of context'.
"The amendment was put forward in good faith, as part of the negations of the extended runway. That hasn't come to happen, therefore we can't make the savings we were expecting.
To implement an amendment which was put in place for a rehabilitation of the airport, that has not happened, seems wrong to me."
He says locals and tourists will be negatively impacted.
"People were moaning about the fares before, never mind adding to them now.
Based on what was said to us, you're looking at potentially a fare increase of about £90 to Southampton, about £450 return.
That's going to affect everybody, it is not affordable, you can get to New York for that."
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