On 2 July, a new and defining stage in the development of Argentina’s Carem25 Project began, with the signing of the contract for the completion of the reactor building concluded between the National Atomic Energy Commission (CNEA) and Nucleoeléctrica Argentina SA (NA-SA). The agreement was signed by CNEA president Adriana Serquis and NA-SA president José Luis Antúnez. Through the new contractual relationship the Argentine NPP operating company reconstitutes itself as a contractor for CNEA in the construction of the building, a role it had played in the first stage of that work from 2014 to 2017.

Adriana Serquis commented that "the signing of the contract entrusting Nucleoeléctrica Argentina to complete the construction of the civil works of Carem25 represents a very important milestone in the beginning of the reactivation of the nuclear sector." He added that “it is an excellent auspice for a joint path in which we can strengthen ties so that the CNEA can continue carrying out other projects.” He said CNEA was “passionate about the possibility of once again having a role in articulating existing capacities”.

José Luis Antúnez stated that "the objective of collaboration with the CNEA is part of our Plan of Action, recently approved by the National Executive Power." In that sense, he remarked that "just as we did previously, we are returning to accompany CNEA in the Carem Project."

In mid-2020, a "transition" contract had been signed, from which the work teams of the Carem Works Directorate Management (responsible for the integral direction of construction) and the Nuclear Project Management Unit of NA-SA began a process of ordering and analysis of the technical documentation related to the building and the degree of progress reached with the previous contractor. This analysis included a survey of materials and the state of the facilities, as well as the pending subcontracts and the employment situation of the workers who had been laid off and with whom the gradual reinstatement was agreed.

The overall objective of that pre-contract was to establish the basis of what would be the definitive agreement from which NA-SA resumes the execution of the construction, under the direction of CNEA. This new contract establishes a duration of 36 months to complete the reactor building, reactivating the synergy between CNEA and NA-SA that in the past made it possible to start construction and achieve important progress.

According to CNEA, in this new stage, the aim is to take advantage of the greater degree of advancement in engineering and, in general, all the experience obtained by both actors in recent years, as well as sustaining and consolidating the good relationship that has been forged between the teams of work and with the groups of workers. These factors “will undoubtedly favour the fulfilment of the fundamental objective of finishing the work and starting up the Carem prototype. "It is a joy that we have finally been able to sign this contract," said Carem Area Manager Sol Pedre. "We see a good willingness on the part of NA-SA to collaborate with the completion of Carem, even beyond what has to do with the work, which I consider a very good sign for the project and for the CNEA as a whole."

Carem (Central ARgentina de Elementos Modulares) is Argentina's first domestically-designed and developed 32 MWe nuclear power unit. As well as relying on passive safety systems, Carem's entire primary coolant system is contained within the single self-pressurised vessel and uses free convection to circulate the coolant. This eliminates the need for devices such as pumps within the primary circuit and decreases the extent and complexity of the piping system required, as well as reduces the possibility of accidents involving a loss of coolant.

Before work was suspended, it was in line to be the world’s first operating SMR. The government licensed it as a prototype in 2009. Development started in 1980 by CNEA and technology company INVAP and it was first announced in 1984. Progress slowed in the early 2000s but a 2006 government decree made the Carem25 programme a national priority. A second executive order in 2008 made the project directly responsible to the President of Argentina.

Initially, Carem25 was expected to start up in 2017, but this was put back to 2020. Then, in 2019 contractor Techint Engineering & Construction stopped work alleging late payment from the government, design changes and late delivery of technical documentation. In April 2020, it was announced that construction was to resume.

According to the CNEA, the Carem facility will include facilities for training operators and performing other research. CNEA said that at least 70% of components and related services are being be supplied by domestic companies and will fully meet international standards.

Following its successful operation at Atucha, Argentina intends to build additional units for domestic use and export. CNEA has plans to build a 100MWe Carem reactor near Formosa in Argentina and a larger 300MWe version intended for export.