As many as 20,000 British travellers remain stranded in the Egyptian resort of Sharm el-Sheikh following the crash of a Russian airliner at the weekend.

The UK Foreign & Commonwealth Office has advised against “all but essential travel” to the destination as investigations into the cause of the accident continue.

Foreign secretary Philip Hammond said that there was a “significant possibility” the Airbus plane, which crashed over the Sinai on Saturday, killing all 224 people on board, was brought down by an explosion.

US officials have also suggested a bomb was planted on the plane by Islamic State or an affiliate.

However, both Russia and Egypt have urged caution over speculation as to the cause.

The unilateral decision to delay the flights from the destination comes as British prime minister David Cameron meets Egyptian president Abdel Fatah al-Sisi in Downing Street.

The British government flew additional consular staff to Sharm on Wednesday to help holidaymakers who might be stranded following its decision to halt all flights to the UK pending security checks at the airport.

In a statement ABTA said: “We are liaising with the UK government about the halt to flights in and out of Sharm el Sheikh airport and how we can assist our members and customers in resort, or those due to travel out.

“We will provide further updates when they are available.”