Olympic Day is marked on June 23 every year, celebrating the anniversary of the IOC's formation in Paris in 1894 by Pierre de Coubertin.

With celebrations curbed by the coronavirus pandemic, Bach shared a video message to mark the occasion. 

"Celebrating Olympic Day may feel very different from all previous years, but at the same time, on this Olympic Day, our message of the power of sport to bring hope and optimism to everyone resonates even stronger," he said.

"Let us join together to use this power of sport to prepare the postponed Olympic Games Tokyo 2020 as a moment of solidarity and resilience of humankind.

"We are all in the same situation right now.

"With the global coronavirus crisis, all of us are living with much uncertainty about the future. 

"In these difficult times, we need the values of sport, our shared Olympic values of excellence, friendship, respect and solidarity, more than ever."

The IOC launched the "Stay Strong" campaign to help people around the world get through the pandemic together. 

A number of initiatives have been held as part of the campaign, including a 24-hour digital Olympic workout which took place today. 

Bach reiterated the message of the campaign in his message.

"The Olympic Flame can be the light at the end of the dark tunnel that we all find ourselves in now," he said.

"On Olympic Day, we are sending this Olympic message to everybody. 

"Please stay strong, stay active, stay healthy. 

"In this Olympic spirit, I wish you all a wonderful and pleasant Olympic Day 2020."

The IOC also marked Olympic Day by joining with the United Nations and the World Health Organization (WHO) for an initiative called "#HEALTHYTogether".

It is hoped that people and communities around the world will be encouraged to live healthier lifestyles while reducing the spread of coronavirus.

As part of the campaign, Olympic athletes will deliver public health messages in the coming weeks.