Link between PO for Material and a PO for a carrier

Hi experts,

I need to create a link between PO for Material and a PO for a carrier.

I explane the case

We have a supplier for a Raw material that do not supplie the transport to us so we need a carrier to make the shipment to us.

I need to create a PO for the supplier (A) for the raw material + a PO for the carrier (B) and I need that the sum of these costs (A+B) have impact on the material master (A) otherwise if I compare all the suppliers for the raw material A the data are inconsistent because this is the only supplier that don't include the transport.

How I can do that?