The plans include extending the runway safety areas
Delay on upgrades to Guernsey's airport runway could cause serious problems for the island, the Airport Users Group chairman has said.
Dudley Jehan said: "The runway could further deteriorate and the CAA could change the licensing regulations. That would be serious for the island."
Changes by the regulator, the Civil Aviation Authority (CAA), could stop certain planes landing in the island.
The group welcomed the States' decision to spend £81m improving the runway.
Deputies approved the Public Services Department's plans to move the runway to the west and extend the safety areas on either side.
Mr Jehan said an amendment to the proposed plans, which gave all States Members the final say on who gets the contract to do the work, means it was likely to be delayed again.
Deputy Al Brouard, who was unsuccessful in his attempt to get a planning enquiry before the project went ahead, said he felt it was time to stop arguing and get on with the work.
He added he felt the plans the States settled on are at least better than the original proposals put forward by the Public Services Department earlier this year.