Travellers returning to the UK from Switzerland could have to self-isolate, if the government decides to remove the country from its quarantine exemption list.
UK ministers are meeting later to discuss any changes to the list of safe travel corridors.
There is also concern about a rising number of Covid cases in Gibraltar.
The requirement to quarantine for 14 days has already been applied to people coming from Switzerland to Scotland.
It follows a rise in infections in the country.
The UK considers imposing quarantine conditions when a country’s rate of infection exceeds 20 cases per 100,000 people over seven days.
Switzerland is currently over that threshold, with a seven-day rate of 21.2.
Quarantine rules are set by each UK nation separately but restrictions imposed in England following the ministers’ meeting are also likely to be adopted by Wales and Northern Ireland.
Swiss Tourism Federation director Barbara Gisi has said with over 1.6 million Britons travelling to the country last year, the UK is the third largest foreign market for Switzerland.
“Swiss tourism cannot afford to do without guests from abroad in the long term,” she said.
Is Gibraltar next?
The number of cases in Gibraltar is causing increasing concern in government.
I’m told the jump in cases in recent weeks is significant; and now above 100 per 100,000. The threshold at which quarantine is discussed is 20 per 100,000.
But as a British Overseas Territory, the move would be diplomatically controversial. One source described the decision as a “sticking point” in the weekly conversations on travel corridors.
It is also understood there is discussion about requiring people arriving from Jamaica and the Czech Republic to quarantine.
Cuba is among the countries where there has been a decline in case numbers – and its possible it could be added to the quarantine exemption list.
But I expect at least one part of the UK – and possibly others – to announce quarantine measures later today.
Speaking on BBC Radio 4’s Today programme, Chief Minister of Gibraltar Fabian Picardo said cases appeared to be rising in the territory because they were doing more testing than most other places.
He said they had been “very successful at identifying cases of the virus and exercising controls in terms of imposing self-isolation”.
“We have no one in hospital we have no one in ICU, we have had no one die from the virus.”
He said imposing quarantine rules would be “a huge inconvenience” not just to tourists but also people travelling to Gibraltar for work and study.
The Department for Transport introduced the compulsory 14-day quarantine for arrivals from overseas in early June.
In the following month, the four UK nations unveiled lists of “travel corridors”, detailing countries that were exempt from the rule.
Since then the governments have regularly updated that list, adding and removing countries based on their coronavirus infection rates and how they compare with the UK.
Last week quarantine restrictions were lifted on those returning from Portugal, but added for travellers coming back from Croatia, Austria and Trinidad and Tobago.
People who do not self-isolate can be fined up to £1,000 in England, Wales and Northern Ireland, and £480 in Scotland, and there are fines up to £5,000 for persistent offenders.