The World Health Organization (WHO) has called for caution from anyone attending the upcoming Olympic Games in Tokyo in a bid to combat the spread of COVID-19.

The warning comes after the WHO blamed the European Championship for a rise in COVID-19 cases across Europe.

Crowds inside football stadiums, pubs and bars in the host cities were cited as the reason for an increase in infections by the WHO.

Tokyo is preparing to welcome tens of thousands of athletes, journalists and staff from around the world for the Olympics, which are due to open in just 20 days' time.

There are fears from medical experts in Japan that hosting the event could help accelerate the spread of COVID-19.

Last month, the WHO offered its support to the Games, praising coronavirus countermeasures outlined by organisers in their playbooks, which will guide how events will take place.

Overseas fans have been barred from attending the Olympics and Paralympics due to concerns over COVID-19.

Organisers are able to allow up to 10,000 domestic spectators or half the venue capacity of watch events at the Games – a move which approved by the Japanese Government when state-of-emergency measures were lifted last month.

Tokyo 2020 is now considering preventing spectators from attending evening events amid concerns over the COVID-19 pandemic.

A meeting is due to take place on Thursday (July 8) when Tokyo 2020, Tokyo Governor Yuriko Koike and IOC President Thomas Bach are expected to discuss spectator presence.

Tokyo, which is under quasi-emergency measures, registered a further 716 coronavirus cases in the past 24 hours.

The Japanese capital is reporting an average of 432.6 cases per day in Japan - dropping from 705.8 in May, according to the Mainichi.

Almost 16 million people in Japan have been fully vaccinated against COVID-19, which equates to 12.7 per cent of the population, while 24 per cent have received at least one dose of a vaccine.

The IOC has claimed more than 80 per cent of people inside the Athletes' Village will either have been vaccinated or be in the process of inoculation in time for the Games.

The Tokyo 2020 Olympics are scheduled to run from July 23 to August 8, before the Paralympics take place between August 24 and September 5.