"The impact on our viewing figures is extremely high which is causing us a damage we won't accept", Casas said.

Franceinfo reported TF1 was preparing a law suit against Canal +.

When contacted by Reuters, a TF1 spokeswoman said the group was "seriously considering" to take legal action.

Canal+ last week said it ended the partnership because the price TF1 asked for to continue delivering its programmes was too high.

Casas on Monday said the move affected some ten million viewers.

(Reporting by Dominique Vidalon, editing by Tassilo Hummel)