“The fight against jihadism is without doubt the big challenge of our generation,” Manuel Valls said, flanked by the interior and justice ministers.
The plan, which will cost an additional 40 million euros ($45.5 million) by 2018 on top of the current funding, aims to double existing efforts to try to help people already in jihadist networks or those likely to join such groups.
Valls said the first de-radicalisation centre could be set up by this summer.
The measures are a response to the deaths of 147 people in jihadist attacks in France last year.
Jihadist gunmen stormed the Paris offices of Charlie Hebdo satirical newspaper and a Jewish supermarket in January 2015, killing 17 people, and then 130 people were killed in coordinated attacks on the capital claimed by the Islamic State group last November.
Both sets of attacks were carried out mainly by French citizens who had become radicalised and fought abroad alongside jihadist groups.
The authorities consider nearly 10,000 people in France to be radicalised and capable of violent actions, according to Le Parisien newspaper.