Alliance Infrastructure Spokesperson Kellie Armstrong MLA has said Flybmi's announcement that it has gone into administration should be more than a warning sign over the continued ambiguity around Brexit.
The airline announced on Saturday night it had ceased operating, cancelling all flights with immediate effect, citing rises in fuel and carbon costs and uncertainty over Brexit as key reasons.
Kellie said: "With Parliament no closer to agreeing a way forward on Brexit, this is a clear example of the damage that indecision is causing to Northern Ireland and the UK as a whole.
"Brexit is the final straw that has broken Flybmi, throwing into jeopardy the current City of Derry/London route - meaning we could be facing another disappointing loss in our air travel capabilities, leading to a knock-on effect on our business community.
"Only a few days ago the Sec of State and Minister for Transport were congratulating themselves for providing investment for the Derry to London route. Without a secure carrier that action now appears somewhat pointless.
"I'll be working to ensure all those affected are fully aware of the rights and other options open to them, as all passengers should be able to seek reimbursement from card issuers or through travel insurance.
"If any passenger is unable to get a full reimbursement they can contact me via my constituency office or seek assistance from the Consumer Council."