Mr. Sarkozy spoke of what he said were the dangers of uncontrolled immigration and radical Islam, a theme he has been mining in recent weeks in an apparent attempt to attract supporters of far-right leader Marine Le Pen, who took 17.9% of the votes in the first round of the election.
"What we do know is that if you formulate it in the right way, it actually forms kind of the bedrock of the mining industry - it's a hugely used commercial explosive, " he told the BBC World Service.