For the performance of a conventional contract, to procure goods, as well as to attract subcontractors or co-executors, is required by Law No. 44-FZ.
If it is a question of a contract, then it is possible to purchase goods, works and services within the framework of Law N 223-FZ. At the same time, the volume of purchases should not be more than necessary for the fulfillment of obligations.
A similar opinion was expressed by the Ministry of Finance earlier.
Recall that unitary enterprises can carry out part of their purchases under Law N 223-FZ, only if they have placed a provision on procurement in the EIS.
Document:
Letter No. 24-04-08 / 87329 of the Ministry of Finance of the Russian Federation of December 22, 2017