The French League initially banned PSG from this year's edition after some of their fans held up an abusive banner during their 2-1 win over northern club Lens in the final at the Stade de France in March.
A civil court later quashed that decision and the two sides meet again at Parc des Princes on Wednesday.
"We are out for revenge after our defeat in the final," Leclercq told reporters.
"The whole region suffered from this story... It is not natural to let PSG compete in this Cup."
Lens mayor Guy Delcourt said he would not attend the game in protest at PSG's participation in the Cup.
"I expected the French League chairman (Frederic Thiriez) to make a strong statement before the game, he did not. The same thing with (Sports Minister) Bernard Laporte," he told daily L'Equipe.
"I still deeply hold a grudge against everybody in French football."
The abusive banner referred to a film about the life of the Ch'tis, a nickname for the people of northern France, and it read: "Paedophiles, unemployed, inbred: welcome among the Ch'tis".
"I won't speak about the banner when I will talk to the players before the game," Lens coach Jean-Guy Wallemme told reporters.
"The defeat was harsher than the banner story. The penalty we conceded in the last minutes of the final was also very painful."
"I don't think those kinds of statements are really appropriate. It is a clumsy initiative but I don't have anything against them," he told reporters on Tuesday.
"I think it is normal we were allowed to compete. I will say it again and again."
