Macron is trailing his predecessor by 1 percentage point, and he went on to be named France's least popular leader in recent history.
More than 3,500 Canadian soldiers died during the Battle of Vimy Ridge in France.
The message seemed aimed at China, which claims almost all the South China Sea and which has fueled concern in Japan and the West with its growing military presence in the waterway.
Hollande said he wanted to make sure France wasn't won over by the far-right leader's presidential campaign.
It won't be plain sailing for the independent candidate, but the latest polls show Emmanuel Macron is the one to watch.
The party's primary race is underway, and a candidate will be chosen at the end of this month.
Valls resigned after announcing his candidacy for the 2017 presidential elections.
Sites could be punished with a fine or even with prison sentences.
Hollande's decision leaves an opening for a Socialist to challenge Marine Le Pen and Francois Fillon.
If the former prime minister prevails over Alain Juppe, he will face National Front's Marine Le Pen and a Socialist candidate.
Unpopular president is forecasted to lose a three-way race between Marine Le Pen and the winner of the Les Republicains' primary.
French troops are deployed across North and West Africa to tackle militant groups.
Socialist incumbent president is expected to declare whether he will stand by December.
The Russian leader announced he will return to four-way talks.
The three will speak on the sidelines at the upcoming G20 summit in China.
Angela Merkel, Francois Hollande and Matteo Renzi called for closer security cooperation.
Matteo Renzi will host Angela Merkel and Francois Hollande to discuss reverberations from Brexit vote.
French president admits in a new book that the job 'has been a lot harder than I had imagined.'