British airline partners Thomas Cook, Thomson and First Choice have canceled all summer flights to Tunisia, while EasyJet and Monarch are also expected to cancel flights.

The Embassy of the United Kingdom has issued a travel warning to all British citizens in Tunisia, strongly discouraging tourists from visiting the country and urging those within the country to leave. This updated travel warning follows the June 26 attack in Sousse during which 38 tourists were killed by terrorists, 30 of which were British.

"While we do not have any information suggesting a specific or imminent threat, since the attack in Sousse the intelligence and threat picture has developed considerably, leading us to the view that a further terrorist attack is highly likely," Philip Hammond, the British foreign secretary, told the BBC .

However, Tunisia's ambassador to the UK criticized the decision by saying the advisory was "what the terrorists want." The ambassador went on to point out that the travel warning and encouraged evacuation would have grave effects on Tunisia's tourism industry.

For his part, Hammond said that although the British government was working with the Tunisian authorities to help prevent future incidents, much more work must be done to ensure security.

"We judge that more work is needed to effectively protect tourists from the terrorist threat. Taking all these factors together, we judge that it is right and prudent to make this change today.”

The tourism sector is responsible for 14 percent of Tunisia's economy, employing some 400,000 individuals throughout the country. According to the latest reports, there are currently between 2,500 and 3,000 British tourists in Tunisia on organized tours. An additional 300 or so are traveling around the country independently.

Extra flights are being arranged to help evacuate the British citizens still in Tunisia. However, it seems the number of British tourists has already dwindled significantly as 25,000 are normally expected during this time of year.