UK travellers to Croatia will have to spend two weeks in isolation under new rules to combat coronavirus.
The UK is one of 11 nations affected by the change.
The disclosure came in updated Foreign Office travel advice.
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The FCO said: “On 12 March the Croatian government announced that it will introduce with immediate effect a compulsory 14-day period of self-isolation for all foreign nationals arriving from the following destinations – the United Kingdom, France, Germany, Switzerland, Spain, Austria, Netherlands, China, the Republic of Korea, Japan and Singapore.
“Foreign nationals who do not have a residence in Croatia will be asked for proof of an accommodation booking.”
Around 860,000 British travellers visited the country in 2018.
Meanwhile, the FCO warned that there was a “high risk” of Britons being put into 14 days of quarantine as part of travel restrictions imposed by Vietnam.
“There is also a risk of British nationals being turned away from, or asked to leave, hotels in Vietnam,” the FCO added.
The Asian country suspended its visa waiver scheme for Britons on Thursday, with reports that e-visas have also been suspended.
The FCO added: “The Vietnamese embassy in London say that it is possible to get a visa, but there is uncertainty around the replacement process and timeline for such applications.”