UK aviation bosses said they are "confident" air travellers will not face a repeat of the severe ash cloud, which grounded flights in 2010, should Iceland's Bardarbunga volcano erupt.
Iceland's authorities have already evacuated the area after geologists said about 300 earthquakes had been detected there since Tuesday.
When Iceland's Eyjafjallajokull volcano erupted European air space was shut down for six days causing travel chaos and losses of £2 million.
But UK air traffic control company Nats and the UK's Civil Aviation Authority (CAA) said the UK is much better prepared to deal with any ash cloud crisis than four years ago.
A Nats spokeswoman said: "We are monitoring the situation in Iceland and we don't know how serious it will get and just where any ash cloud will travel if the volcano erupts.
"Even in a worst-case scenario we are in a much better position to deal with this than we were in 2010."
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