Regulus completes mineral resource estimate for Coimolache/AntaKori copper-gold

VANCOUVER, British Columbia, June 30, 2026 (GLOBE NEWSWIRE) -- Regulus Resources Inc. (“Regulus” or the “Company”, TSX-V: REG, OTCQX: RGLSF) is pleased to announce that the Company, in collaboration with Compañía Minera Coimolache S.A. (“ Coimolache ”, collectively with Regulus the “ Parties ”) have completed the first phase of the collaboration agreement previously announced on July 25, 2024. The agreement was designed to evaluate the viability of an integrated Coimolache Sulphides/AntaKori copper-gold project (“ Integrated Sulphide Project ”), starting with the completion of a mineral resource estimate (“ MRE ”), with the option, upon mutual agreement of the Parties following the completion of a MRE, to complete a preliminary economic assessment (“ PEA ”). The results of the MRE and PEA (should the Parties agree to move forward) can only be publicly released upon mutual agreement of the Parties and regulatory approvals.

John Black, Chief Executive Officer of Regulus, commented: “The completion of the Integrated Resource Estimate constitutes a milestone for both Regulus and our neighbours. This is the first fully unconstrained resource estimate created by a third-party, removing property boundaries and focusing solely on mineralization. While we don’t anticipate the report being made public, the completion of the study still represents a significant step forward for the region, as it allows all parties to understand the value that can be unlocked in the district via collaboration.

While we decide next steps regarding our agreement with Coimolache, we continue to de-risk the project on the ground via advancing our community programs to set the stage for future development.” The MRE was completed by SRK Peru, which has developed an internal report that has been distributed to the Parties. The Company will provide no further updates regarding discussions with Coimolache until decisions are made regarding the MRE and PEA. The Company cannot provide a timeline for a decision at this time.

The AntaKori Project The AntaKori project, located in Cajamarca, Peru, currently hosts a resource with indicated mineral resources of 250 million tonnes with a grade of 0.48 % Cu, 0.29 g/t Au, 7.5 g/t Ag, and inferred mineral resources of 267 million tonnes with a grade of 0.41 % Cu, 0.26 g/t Au, 7.8 g/t Ag. The AntaKori project is immediately adjacent to and interfingered with mineral concessions owned by Coimolache. The last mineral resource estimate on the AntaKori project was completed under a now-expired agreement with Coimolache whereby Regulus could use a portion (but not all) of the Coimolache drill database to develop a partially integrated resource estimate, but only report resources from the AntaKori claims.

A total of 71,762.04 m of drilling (historical + Regulus) has been completed on the AntaKori project from 1997-2022. Since the 2019 AntaKori resource estimate was completed, Regulus has completed 31,666.99 m of drilling on the AntaKori project. Qualified Person The scientific and technical data contained in this news release pertaining to the 2019 AntaKori mineral resource estimate has been reviewed and approved by Dr. Kevin B. Heather, Chief Geological Officer, FAusIMM, who serves as the qualified person (QP) under the definition of National Instrument 43-101.

ON BEHALF OF THE REGULUS BOARD (signed) “John Black” John Black CEO and Director Tel: +1 (604) 685-6800 Email: info@regulusresources.com For further information, please contact: Regulus Resources Inc. Ben Cherrington Tel: +44 7538 244 208 Email: ben.cherrington@regulusresources.com About Regulus Resources Inc. and the AntaKori Project Regulus is an international mineral exploration company run by an experienced technical and management team. The principal project held by Regulus is the AntaKori copper-gold-silver project in northern Peru. The AntaKori project currently hosts a resource with indicated mineral resources of 250 million tonnes with a grade of 0.48 % Cu, 0.29 g/t Au and 7.5 g/t Ag and inferred mineral resources of 267 million tonnes with a grade of 0.41 % Cu, 0.26 g/t Au, and 7.8 g/t Ag (independent technical report prepared by AMEC Foster Wheeler (Peru) S.A., a Wood company, titled AntaKori Project, Cajamarca Province, Peru, NI 43-101 Technical Report , dated February 22, 2019 - see news release dated March 1, 2019).

Mineralization remains open in most directions. For further information on Regulus Resources Inc., please consult our website at www.regulusresources.com . Forward Looking Information Certain statements regarding Regulus, including management's assessment of future plans and operations, may constitute forward-looking statements under applicable securities laws and necessarily involve known and unknown risks and uncertainties, most of which are beyond Regulus' control.

Often, but not always, forward-looking statements or information can be identified by the use of words such as “plans”, “expects” or “does not expect”, “is expected”, “budget”, “scheduled”, “estimates”, “forecasts”, “intends”, “anticipates” or “does not anticipate” or “believes” or variations of such words and phrases or statements that certain actions, events or results “may”, “could”, “would”, “might” or “will” be taken, occur or be achieved. Specifically, and without limitation, all statements included in this press release that address activities, events or developments that Regulus expects or anticipates will or may occur in the future, including the development of the AntaKori project described herein, and management's assessment of future plans and operations and statements with respect to the completion of the anticipated exploration and development programs, may constitute forward-looking statements under applicable securities laws and necessarily involve known and unknown risks and uncertainties, most of which are beyond Regulus' control. These risks may cause actual financial and operating results, performance, levels of activity and achievements to differ materially from those expressed in, or implied by, such forward-looking statements.

Although Regulus believes that the expectations represented in such forward-looking statements are reasonable, there can be no assurance that such expectations will prove to be correct. The forward-looking statements contained in this press release are made as of the date hereof and Regulus does not undertake any obligation to publicly update or revise any forward-looking statements or information, whether as a result of new information, future events or otherwise, unless so required by applicable securities law. Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.

Globe Newswire June 30, 2026 - 4:00 AM PDT News by QuoteMedia www.quotemedia.com