Japan’s failed attempts to contain the country’s worst nuclear disaster are raising concerns that the crisis could scupper Tokyo’s chances of hosting the 2020 Olympic Games.

The crisis at the Fukushima Daiichi Nuclear Power Station has intensified just as the International Olympic Committee (IOC) prepares to decide at its meeting in Argentina this weekend which city will host the world’s most prestigious sporting event.

Akira Amari, state minister in charge of economic recovery, said on TV Asahi on Tuesday night that the government would spend ¥ 47 billion ($ 470 million) to tackle Japan’s “national crisis,” referring to the latest leak at the plant.

Last week, the Nuclear Regulation Authority increased the severity of the leak from level 1 to level 3, or “serious incident,” following the discovery of 300 tonnes of leaked radioactive water from a storage tank.

The Japanese bid team has consistently denied that the nuclear crisis would damage Tokyo’s Olypmic candidacy.

“I do not believe it would directly affect our chances to host the Games,” Tokyo Governor Naoki Inose said.

Inose has already left Tokyo for the IOC meeting in Buenos Aires this weekend, where Tokyo will make a final presentation for its bid against rivals Madrid and Istanbul.

Tsunekazu Takeda, the chief of the Tokyo 2020 bid, told IOC members the Japanese capital “is completely unaffected” by the nuclear disaster.

In Buenos Aires on Wednesday, Mr. Takeda had to bat off repeated questions from reporters in Buenos Aires about Fukushima, insisting that “the radiation level in Tokyo is the same as in London, Paris, New York.” Others are not convinced.

In Tokyo, a civic group measured radiation levels at 37 sites planned for the 2020 Games. At many of the sites, the group detected higher levels of radiation than before the 2011 disaster, and also found radioactive caesium, which was almost absent before, at a soccer stadium 30 kilometres north of the capital.

“Whether you support Tokyo’s Olympics bid or not, we have a moral responsibility to show the international community facts about radiation contamination in Tokyo,” Takehiko Tsukushi, a member of the group, said.

Ryusaku Tanaka, a veteran journalist who has covered the nuclear disaster from the beginning, said the link between the nuclear crisis and the Olympic bid is clear.

“Do athletes who are taking extra care in protecting their health want to come to radiation—contaminated Japan?” Tanaka asked in a recent article.

The government and major media outlets have downplayed the recent crisis, while highlighting the victories of Japanese athletes at the 2012 London Games, according to Setsuko Kuroda, a member of No Nukes Fukushima Women.

“There is no time for the Olympics,” Kuroda said. “If Japan can afford to hold the Olympic Games, the government should spend that money to evacuate children from Fukushima immediately.” Japanese Prime Minister Shinzo Abe has said that the world would be “closely watching” how Japan handles the Fukushima nuclear crisis.

Mr. Abe is due to address the Fukushima issue in Japan’s final presentation in Buenos Aires, an acknowledgement that the IOC is watching closely too.

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