Article L2511-43 of the French General Code of Local Authorities
The arrondissement mayor commits and authorises expenditure entered in the special statement once it has become enforceable, in accordance with the rules applicable to expenditure authorised by the mayor of the commune or by the mayor of Paris. If the arrondissement mayor fails to authorise a compulsory expenditure provided for in the budget, the mayor of the commune or the mayor of Paris gives him formal notice to do so….