Dozens of flights to and from the east coast of America have been cancelled due to the threat of Hurricane Sandy.
British Airways has grounded all flights to and from the US Eastern Seaboard, including New York, Baltimore, Washington, Boston and Philadelphia. A number of BA flights from the US to London have also been halted.
Virgin Atlantic has cancelled flights to and from New York, Washington and Boston.
A statement on BA's website said: "We understand that customers may be disappointed, however their safety is our highest priority. We are offering the option to rebook or receive a refund to those customers whose flights are cancelled.
"We have also received reports that public transport links to east coast US airports may be disrupted so advise customers to review their flight and local travel plans before leaving for the airport."
A spokesman for Virgin Atlantic said on Sunday night: "Passenger and crew safety is our number one priority and we are continuously liaising with local authorities to assess the situation and minimise the disruption caused to passengers.
"We advise all passengers to check our website: www.virginatlantic.com for the latest updates and advice."
Heathrow Airport is advising passengers who are due to fly to the US to check the status of their flight with their airline before travelling.
Hurricane Sandy is threatening 50 million people on America's heavily-populated east coast and forecasters warned that New York could bear the brunt of the one-of-a-kind superstorm.
Forecasters warned the megastorm could wreak havoc over 800 miles from the east coast to the Great Lakes. States of emergency have been declared from North Carolina to Connecticut.