The venue which can hold nearly 70,000 spectators is the biggest in Greece after undergoing renovation for the Athens 2004 Olympics and Paralympics, where it hosted the Opening and Closing Ceremonies, athletics and football.

It is due to undergo its first renovation since the Games this year, but the Athens Olympic Sports Complex (OAKA) said inspections had found the famous roof designed by Spanish architect Santiago Calatrava was unsafe.

The Athens Olympic Velodrome at the OAKA, used for track cycling at Athens 2004, has also been closed following similar tests to its roof.

A second inspection is set to follow to further investigate the issue, and the OAKA said its "sole focus" is the safety of athletes and fans.

The Hellenic Olympic Committee (EOE) said the OAKA must continue to be "the heart of Greek sports", and called for safety issues to be resolved quickly.

"Its firm position is that, in addition to the creation of sports facilities, care must also be taken for their maintenance in order to keep them in the best possible condition and safely host athletes," it said.

"At the same time, they should be equipped with modern equipment according to the requirements and development of each sport.

"[The EOE] agrees with the decision of the Minister of Sports, as the safety of the athletes, athletes, fans and workers in the venues is a priority and should not be jeopardised for any reason or purpose.

"[The EOE] requests to speed up the procedures and studies for the stability of the Calatrava constructions, in order to immediately start the restoration works - in case they are required - for the smooth and safe operation of the OAKA."

The Olympic Stadium, opened in 1982 in time for the European Athletics Championships, has hosted several major events including the 1991 Mediterranean Games, 1997 World Athletics Championships and men's UEFA Champions League finals in 1994 and 2007.

It is formerly named after Spyros Louis, who won the first modern Olympic marathon gold for Greece at Athens 1896.

Renovation to the stadium had been planned as part of a €56.3 million (£48.9 million/$59.6 million) fund for improvements to the OAKA.

Concerns over the safety of the Olympic Stadium in 2018 prompted an investigation from Greek authorities and UEFA, after a video appeared to show it swaying during a Champions League match between AEK Athens and Bayern Munich, but the stadium management insisted this was normal.

Athens-based football club Panathinaikos are using the Olympic Stadium for their European home matches this season, with the next scheduled tie against French side Rennes on October 26.

Greece is the birthplace of the Olympic Games at Olympia, approximately 250 kilometres west of Athens.

Athens held the first modern Olympics in 1896, and became the fourth city to host two editions in 2004.