Travellers to Switzerland from 29 countries will from July 6 have to register with the authorities and go into self-isolation to prevent a resurgence of the coronavirus, the government said on Thursday.
The list includes the United States, Sweden, Brazil and Russia, which have been designated as countries with a high risk of infection.
Visitors who have spent time in the named countries in the previous 14 days must notify the Swiss authorities immediately on arrival and then go into quarantine for 10 days, the government said.
The list of affected countries also includes Argentina, Chile, Colombia, Saudi Arabia, South Africa and Serbia. The list will be continually reviewed, the government said.
In Switzerland the number of infections has started to increase in recent days, triggering concerns about a second wave of COVID-19, but its borders with Italy, Austria, Germany and France are currently open.
The country, which has lifted many of its restrictions, including reopening schools and shops, has had 31,967 positive tests for COVID-19 so far, while 1,686 people have died during the epidemic.
Switzerland is in the 26-nation Schengen area which normally has no frontier checks. Unrestricted travel has been allowed between Switzerland and all the other Schengen members, apart from Sweden which appears on the government list.