Article 378 of Civil Code

1 - If the transfer of debt is concluded between the original debtor and the transferee debtor, it shall not be effective against the creditor unless he approves it. 2 - If the original debtor or the transferee debtor notifies the creditor of the transfer and sets him a reasonable period for approving it, and that period expires without such approval being given, the creditor's silence shall be deemed a rejection of the transfer.