Le Pen told The Guardian it is the "responsibility of France to extend a hand to the Walloons," a French-speaking people who live in Belgium, principally in Wallonia.
Le Pen issued a statement Tuesday on Belgium's national day, saying if Belgium can't remain united, Paris should "extend a hand" to Belgium's Francophones, French-speaking residents.
Belgium has gone without an official government since the Dutch-speaking north, where the Flamands live, and the French-speaking south, home to the Walloons, failed to agree on how the country should be run since an election more than a year ago.
"The political situation that Belgium is going through is getting worse, appears to have no solution and has left both Walloons and Flamands in a terrible uncertainty," Le Pen said.
"If Belgium is going to split, if Flanders pronounces its independence, which seems more and more credible a possibility, the French republic would do well to welcome Wallonia to its heart."