Japan's Olympics minister says organizers have not worked out where to place the ceremonial cauldron in Tokyo's new flagship stadium.
The wooden interior of the new design means installing an internal
cauldron could violate Japanese fire codes.
The stadium has been hit by delays and controversy over the cost
of an earlier design by Zaha Hadid.
A cheaper design, by Japanese architect Kengo Kuma, was chosen in
December last year.
The new design will cost 149bn yen ($1.2bn; £825m) to build.
Ms Hadid's plan would have cost 252bn yen, making it the world's
most expensive sports venue.
The International Olympic Committee deadline for completion is
January 2020, ahead of the Games' start in July that year.
"It appears things were proceeding under the old plans
without much discussion [of where to put the cauldron,]"
Olympics Minister Toshiaki Endo said.
"The lighting of the flame is the main event of the Olympics.
As for exactly how it will be done and where the cauldron will be,
that will be discussed at a later date," he added.
He said that he hoped a solution to the problem would be found
before April. Mr Endo will head a panel set up to review the situation of the
The International Olympic Committee stipulates that the cauldron
should be placed so that it is easy to see for spectators.
Designers had considered placing the cauldron outside the stadium,
but this was met with opposition from Japan's Olympics committee.
The Olympic flame is lit in Olympia, Greece, before traveling
across the world in a torch relay. The lighting of the Olympic cauldron by the final torchbearer
marks the start of the Games.
If all goes according to plan, visitors to the 2020 Tokyo Olympic
Games will be awestruck before the sporting contests even begin.
Attendees will be shuttled around the city by self-driving taxis.
They’ll enter a newly built national stadium with the swipe of a
pass, get verified by facial recognition software and be guided to
their seats in one of 10 languages on a smartphone app.
They may gaze
up at the night sky from anywhere in Tokyo to see an artificial
meteor shower show unfolding 50 miles above their heads.
Concerted efforts are under way to realize these and other
innovations and emulate the enviable legacy of technological
superiority and reputation rebuilding that emerged from the last
Summer Games Japan hosted, in 1964.
Olympic organizers, innovators,
entrepreneurs and academics are working on ambitious projects that
could enhance Japanese society and beyond long after the closing