Newcastle Airport says an independent Scottish government could damage the region's chances of attracting new routes.
The SNP has indicated it would like to cut the level of Air Passenger Duty (APD) if it wins independence in a referendum in 2014.
Graeme Mason, the airport's Planning and Corporate Affairs Director, says if APD is cut north of the border, passengers could choose to fly from Edinburgh and Glasgow instead of Newcastle. In turn, airlines could choose Scottish airports over English ones for new routes.
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Kerrie Gosney brings you Monday night's forecast
North East parents are most likely to raid their children's piggy banks to pay for things such as parking, takeaways and the tooth fairy.
Warmer air feeds in from the south as this week progresses. Temperatures into the high teens by the end of the week