text: **II.23.3. Interest on late payment**
  
  If the contractor does not honour the obligation to pay the amount due by the date set by 
  the contracting authority in the debit note, the amount due bears interest at the rate 
  indicated in Article II.21.8. Interest on late payments will cover the period starting on the 
  day after the due date for payment and ending on the date when the contracting authority 
  receives the full amount owed. 
  
  Any partial payment is first entered against charges and interest on late payment and then 
  against the principal amount. 
  
  **II.23.4. Recovery rules in the case of joint tender**
  
  If the contract is signed by a group (joint tender), the group is jointly and severally liable 
  under the conditions set out in Article II.6 (liability). The contracting authority shall send 
  the debit note first to the leader of the group. 
  
  If the leader does not pay by the due date the whole amount, and if the amount due cannot 
  be offset or can only be offset partially in accordance with Article II.23.2 (a), then the 
  contracting authority may claim the amount still due to any other member or members of 
  the group by respectively*notifying*them with a debit note in conformity with the provisions 
  laid down in Article II.23.2. 