Before having relations with our non-Muslim spouse, should we say a dua to protect us from evil?

We know that when we are going to have relations with our spouse that we should always say a dua for Allah to protect us from evil. Question is, how does this work if a Muslim is married to a non-Muslim (but of the people i.e a Christian or Jew)? - Does he still recite the dua? - Does he still put his hand over her forehead and recite the dua? - Does he just say it to himself? Thank you.