(c) Limitations. An International Agreement Competitive Restriction (IACR) must be used when the terms of the document referred to in DFARS 206.302-4(c) have the effect of requiring the use of other than competitive procedures, even if the agreement, treaty, or written direction does not specifically name a particular source or sources. The contracting officer is authorized to prepare the IACR (see MP5301.601(a)(i)). The contracting officer must include the IACR and a copy of the associated Letter of Offer and Acceptance, once completed, in the contract file.