French Prime Minister Manuel Valls on Tuesday urged a cardinal accused of covering up the sexual abuse of Scouts by a priest, to "take responsibility" in a case which has shocked France.

"The only message I have, without ... taking the place of the Church, of the judges -- because an investigation is underway -- is that he must take responsibility, speak and act," Valls told BFM TV.

Cardinal Philippe Barbarin is one of several senior officials being sued for the alleged cover-up.