The Eiffel Tower will be lit in France's national colours from Friday in tribute to the victims of the Nice truck attack, Paris city hall said.
"The mayor of Paris, Anne Hidalgo, has decided to illuminate the Eiffel Tower in red, white and blue tonight and during the (three-day) period of national mourning," it said in a statement, adding that the illumination would start each night at 10.30pm (2030 GMT).
French Prime Minister Manuel Valls earlier said flags would be flown at half-mast from Friday, and three days of national mourning would begin on Saturday.
He also said the government intended to extend the state of emergency, which has been in place since the November 13 terror attacks on Paris, until October.
The National Assembly, France's lower house of parliament, said that it too will also be lit in the national colours.
At least 84 people were killed, and scores were critically injured, when a 19-tonne truck ploughed through revellers on the seafront in the Cote d'Azur city of Nice, as a crowd watched a Bastille Day fireworks display Thursday night.
The massacre has been described by President Francois Hollande as a "terrorist" attack.