Russian Interior Minister Boris Gryzlov has written a letter to his Belgian counterpart Antoine Duquesne to comment on Belgian authorities' decision to ban entry permits for Russian citizens. According to sources in the Russian interior ministry, Gryzlov was perplexed to learn of this decision. During Duquesne's April visit to Moscow, the sides had discussed the situation with illegal immigration of Russians to Belgium. As a result of the talks, the Belgian side had agreed to set up a bilateral working group to tackle the problem. In his letter, Gryzlov confirmed his readiness to dispatch interior ministry experts to Brussels to attend a session of the working group, which he sees fit to hold in the immediate future.