UK airlines cancelled flights to Tokyo today following the devastating Japanese earthquake.
A British Airways plane heading for Tokyo's Hareda airport had pushed back off the stand at Heathrow today when the airline decided it would not be leaving.
BA also cancelled its daily Heathrow service to Tokyo's Narita airport.
But London-bound BA flights from Hareda and Narita were due to land safely back in the UK later today having left before the earthquake struck.
Virgin Atlantic, which operates daily services to Narita from Heathrow, also cancelled its Tokyo flight today.
A Virgin spokeswoman said: "Narita is about one hour from central Tokyo and we've cancelled our flight VS900 and the return flight VS901 today.
"We do have a flight from Tokyo that left before the earthquake and that will arrive back this evening."
A BA spokesman said: "We decided that we would not operate the Haneda-bound flight (BA007) as a precaution and have also cancelled our flight to Narita."
There are fears that the tsunami could reach as far as Australia, Mexico and Hawaii. Both BA and Virgin said they were closely monitoring the situation.
Virgin Atlantic said its daily London-Tokyo service would not operate tomorrow or on Sunday and that a decision on when its flights to Japan would resume would be made over the weekend.
British Airways was scheduled to operate one flight to Narita and one to Haneda tomorrow. A decision on whether those services would operate was expected later today.
Long-haul holiday company Kuoni said all its UK tourists in Hawaii were safe and well and had been contacted by staff.
A Kuoni spokeswoman went on: "Our people in Hawaii are in Honolulu and they will be moved to higher ground should there be any tsunami danger.
"We have holidaymakers in a number of Pacific areas including Malaysia and Hong Kong and also in Australia. We are aware of the tsunami warnings and are prepared."
She added that Kuoni also had clients in California in an area (western USA) where a lesser tsunami warning has been issued.
The Page & Moy Travel Group said it had a cruise tour operating in the Japan area but holidaymakers had not been affected.
The group, whose holiday companies consist of Travelsphere, Page and Moy and Just You, said alternative arrangements were being made for its clients on existing Far East tours which had been due to visit Japan in the next few days.
Page & Moy went on: "No additional tours are due to leave the UK to Japan until March 27. At the present time these tours are still scheduled to go ahead.
"The US islands of Hawaii and other nations across the Pacific Ocean are also on alert after a tsunami warning was extended across the region.
"At present all tours are going ahead as planned. The situation is being assessed on an ongoing basis. The safety of our customers is our number one priority."