UN secretary general António Guterres, left, with IOC President Thomas Bach ©Getty Images

United Nations secretary general António Guterres has welcomed the start of the Olympic Truce, one week before the Tokyo 2020 Opening Ceremony here.

The traditional gesture calls for the laying down of arms across the world and for fighting to stop during the period of the Games.

"I call on all parties to observe the Olympic Truce during the Tokyo 2020 Olympic and Paralympic Games," said Guterres in a video message.

"People and nations can build on this temporary respite to establish lasting ceasefires and find paths towards sustainable peace.

"In a few days, athletes from around the world will come together for the Olympic and Paralympic Games. 

"They have had to overcome enormous obstacles to participate in the middle of the COVID-19 pandemic. 

"We need to show the same strength and solidarity in our efforts to bring peace to our world. 

"The Olympic Truce is a traditional call to silence the guns while the Games proceed."

The Olympic Truce was due to have come into force last year, but was extended after COVID-19 caused the postponement of the Games to this year.

It was originally passed by the United Nations General Assembly in December 2019 after a formal proposal came from International Olympic Committee (IOC) President Thomas Bach.

Bach is today visiting Hiroshima, the city destroyed by an American atomic bomb in 1945, with a message of peace.

UN General Assembly President Volkan Bozkir last week made a solemn appeal to member states for the truce's observance.

"The Olympic Movement aspires to contribute to a peaceful future for all humankind through the educational value of sport, in particular youth," Bozkir said. 

He described the Games as "the greatest of international sports events as a means to promote peace, mutual understanding and goodwill among nations and peoples, goals that are also part of the founding values of the United Nations".

The truce will remain in force until September 12, seven days after the end of the Paralympics.

The concept of an Olympic Truce dates back to the Ancient Olympics in Greece when it was known as Ekecheiria. 

In the years following the Second World War there were many calls for its revival, but it was not until 1993 that Juan Antonio Samaranch became the first to IOC President to formally request it.

He used his speech at the 1994 Lillehammer Winter Olympics to call for an end to the fighting in Bosnia.

Since then, every IOC President has petitioned the UN for a Truce which lasts for the duration of the Olympic and Paralympic Games.

The Tokyo 2020 Olympic Opening Ceremony is scheduled for July 23.