The United States and Britain said Wednesday a bomb may have brought down a Russian airliner which crashed in Egypt, as the so-called ’Islamic State of Iraq and the Levant’ (ISIL) takfiri group insisted it caused the disaster.

The United States and Britain said Wednesday a bomb may have brought down a Russian airliner which crashed in Egypt, as the so-called 'Islamic State of Iraq and the Levant' (ISIL) takfiri group insisted it caused the disaster.

"A bomb is a highly possible scenario," a US official said. "It would be something that ISIL would want to do," he added.

British Prime Minister David Cameron's office said that "as more information has come to light, we have become concerned that the plane may well have been brought down by an explosive device".

The move comes as Egyptian President Abdel Fattah al-Sisi is set to hold talks with Cameron in London on Thursday, during his first visit to Britain since he led the army's overthrow of his predecessor Mohammad Mursi.

Moscow and Cairo both dismissed ISIL's initial claim it brought down the Airbus A-321 in Egypt's restive Sinai Peninsula, but the takfiri group on Wednesday again insisted they were responsible and promised to reveal how.

Egyptian officials said investigators probing the plane's black boxes had extracted the data from one of them for analysis, but added the other had been damaged and required a lot of work.