BA said earlier on its Web site that flights BA 0873 and BA 0875 at 17:05 Moscow time (13:05 GMT) and 21:15 (17:15 GMT) from Moscow's Domodedovo airport to Heathrow had been cancelled after police reported a terrorist plot involving up to 21 people had been foiled.
"British Airways flight from St. Petersburg to London scheduled for 17:10 Moscow time [15:10 GMT] has been cancelled in the aim [of ensuring] aviation security," the official at Pulkovo airport said.
Police in London said the suspects had planned to bring explosives on board of planes in hand luggage and set them off on flights to the United States. Flights all around Europe into London have also been cancelled.
British Home Secretary John Reid said the alleged terrorists had planned to inflict a "considerable loss of life."
The Russian Ministry of Transportation said there were no intended restrictions on Russian flights to Britain and Russian airlines said they were continuing flights to London as scheduled.