UK: British Foreign Secretary Philip Hammond urged all British nationals to leave Tunisia because "a further terrorist attack is highly likely".
"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," Hammond said.
He further said that an assessment of the security measures in tourist areas found that more work was needed "to effectively protect tourists from the terrorist threat".
According to the British Foreign Office approximately 2,500 to 3,000 UK tourists are still in Tunisia as well as a few hundred British residents.
Read: UK remembers 2005 bombings under shadow of Tunisia
Thirty Britons were among the 38 tourists killed in a brutal attack by a gunman on June 26.
There has not been any specific terrorist threat but travel firms are looking to fly British citizens home over the next few days and some are repatriating their British staff. The Foreign Office has further advised everyone from taking non-essential trips to Tunisia.
However, the Tunisian ambassador to the UK, Nabil Ammar, commented that the decision to leave Tunisia was “what the terrorist want”, and said that it would also harm the country’s tourist industry.
Britons were also urged to get in touch with their tour operators as they were arranging additional flights back to the UK. As for those travelling independently they were advised to return on commercial flights.
The Association of British Travel Agents (Abta) said those due to travel to Tunisia should contact the company they had booked through.
Victoria Bacon, from the association, said, "All Abta members... who have customers in the region have now come forward and made a commitment to get their customers out within the next 24-48 hour period."
One British tourist who arrived in Tunisia the day before the Foreign Office changed its advice said that she was "shocked and disappointed" that she had to leave.
Heidi Barlow, from Derbyshire, is on vacations in Hammamet with her mother. They were supposed to stay until 19 July but were told about the warning to leave from friends and family in the UK.
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The 34-year-old said, "I don't want to leave. I appreciate that if we have to go, we have to go, but I am not worried by the advice. We have these threats in Britain anyway. People have saved up their money and want to get on with their holiday."
She further added, "We have seen all the extra security here and we feel very secure."
Simon Calder, travel editor at the Independent, told the BBC that it would have been a "very tough decision" for the Foreign Office to change its travel advice, because "it... says to the people behind the attack at Sousse, here you are, you've got a victory. You've effectively wiped out Tunisia's tourist industry - or at least a large part of it - for the rest of the summer. That is going to cause economic mayhem."
Thomas Cook has cancelled all its bookings to Tunisia, citing the “safety and well-being” of its customers as its top priority.
Thomson and First Choice said that their British staff working in Tunisia are being returned home, while Monarch Airlines said that it would repartriate all customers in resorts “back to the UK as soon as possible”.
Meanwhile, Tunisian Prime Minister Habib Essid said he would telephone his British counterpart David Cameron on Friday to respond to his government's advice that the North African nation was unsafe for holidays.
"We will ring the British prime minister to tell him we have done everything we can to protect all British interests and those of others countries -- that's our duty," Esebsi told a late-night session of parliament.
"Britain is free to take whatever decision it likes -- it's a sovereign country -- but we too are a sovereign country and we have a position to take."
Essid did not elaborate on what that position might be but he told lawmakers that the British decision would "have repercussions."
Tunisia has brought in a raft of new security measures, including arming tourist police.
This article originally appeared on BBC