The Eiffel Tower was evacuated twice in September The Japanese government has issued a terror alert to its citizens in Europe, following similar warnings from the UK and USA.
The foreign ministry in Tokyo urged people to exercise caution when using public transport or visiting tourist sites.
Security sources warned last week of potential plots on the scale of the Mumbai attacks in 2008.
US authorities have cited France, Germany and the UK as possible targets.
The US state department said on Sunday that a “variety of means and weapons” might be used against official and private interests.
The British Foreign Office said that there was a “high threat” of attack in France and Germany and the government said the threat level in the UK remained at severe.
French officials said there was no reason to raise the current red alert status to scarlet.
In recent weeks, the Eiffel Tower in Paris has twice been evacuated because of bomb threats.
Police say a man has been arrested south-west of the city on suspicion of issuing bomb threats.
Tourists continued to queue at the base of the Eiffel Tower on Monday and a small number of soldiers patrolled the area as usual.
In Italy, Interior Minister Roberto Maroni said the threat level remained high and security forces were watching the situation closely.
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