"In light of this and as a precautionary measure we have decided that flights due to leave Sharm for the UK this evening will be delayed," the spokesperson said, as quoted by the City AM newspaper.
"While the investigation is still ongoing we cannot say categorically why the Russian jet crashed. But as more information has come to light we have become concerned that the plane may well have been brought down by an explosive device."
However, earlier in the day, the Egypt-led commission investigating the crash of a Russian airliner in the Sinai Peninsula said that all speculations concerning the cause of the catastrophe were not based on any concrete evidence.
Egypt is leading the investigation, as the crash took place on its territory, according to Russian Transport Minister Maxim Sokolov. The country-operator of the aircraft (Russia) will also take part in the probe. The country of registration of the aircraft (Ireland) and the manufacturer country (France) are also participating in the investigation.