Sinai plane crash live: David Cameron says Russian jet was 'more likely than not' brought down by terrorist bomb

The Prime Minister says he will discuss British intelligence on the incident with Vladimir Putin

A handout picture taken on November 1, 2015 and released on November 3, 2015 by Russia's Emergency Ministry shows the wreckage of a A321 Russian airliner in Wadi al-Zolomat, a mountainous area of Egypt's Sinai Peninsula (AFP/Getty Images)

Here are the latest updates:

• David Cameron did not inform President al-Sisi of his decision to ground all flights
• Metrojet airline grounds all Airbus 321 planes pending checks
• But a 'significant possibility' Isis was behind crash, Philip Hammond says 
• Hammond says 3,500 British tourists were due to fly out to Sharm today
• 20,000 stranded after Government cancels UK-Sharm el-Sheikh flights
• US official says Isis bomb is 'most likely' reason behind Russian jet crash
• Security sources quoted in US say Isis may have had inside help
• Isis audio message claims it will reveal how it downed jet 'soon'
• Q & A: If it really was a bomb, what does that mean for travellers?
• Rupert Cornwell: What will Putin do next if Isis brought down jet?

David Cameron will chair a second meeting of the Government's Cobra emergency committee later this morning, Downing Street has said, as UK officials scramble to act on "new intelligence" suggesting the Russian jet which crashed on Saturday was brought down by a terrorist bomb.

The Foreign Office says that around 20,000 Britons are stranded in the Egyptian resort of Sharm el-Sheikh after the Government grounded all flights between it and the UK.

No flights are expectecd to leave before at least Friday, while officials said they are working with airlines to find a way to return people to Britain safely.

British experts travelled to Sharm to assess the security situation on Wednesday night, and clearly found measures there wanting. Their evidence was considered by a Cobra meeting on Wednesday night which decided "all but essential" travel through the airport must be halted.

Egyptian authorities have criticised the Government's decision to release a statement, which its foreign minister described as "premature and unwarranted".

But Philip Hammond, the UK Foreign Secretary, said ministers had no choice but to act on intelligence "which we believe represents a threat to British nationals".

He said his angry counterpart in Egypt, Sameh Shoukry, "hasn't seen all the information that we have".