The East Midlands city has been placed on the Belgian government’s “red zone” list of risky destinations following a spike in coronavirus infections.
It is the only place in the UK on Belgium’s list, which also includes regions in Spain and Portugal.
Leicester became the first city in England to have tighter restrictions reimposed on 30 June after a spike in Covid-19 cases.
The city went back into lockdown just days before bars, restaurants and hairdressers were allowed to reopen across the rest of the country on 4 July.
Advice from the Belgian foreign affairs department states that “travel is not allowed” to Leicester and “quarantine is mandatory upon your return”.
The regularly updated advice is based on “currently available information,” according to a note on a Belgian government website.
It also gives the go-ahead for travel to other areas of the EU, the Schengen zone and other parts of the United Kingdom.
Additional reporting by PA