The management of inventory and transportation process at the company level becomes an ongoing issue for business leaders. The Inventory Routing Problem (IRP) is one of the most up-to-date solutions in optimization research field used to reduce logistics cost and create accuracy in inventory management. We introduce in this work a rich variant of the IRP where suppliers have to deliver a set of products to different depots and they will subsequently be distributed from these depots to a set of customers on a finite time horizon with a capacitated homogeneous fleet of vehicles. The objective is to satisfy the customer's request by using vehicles assigned to different depots and allowing split deliveries in the routing decisions. A MILP for a multi-depot, multi-product two-echelon supply chain is proposed and tested on small-sized instances