10 March 2026

CleanTech Lithium PLC ("CTL", CleanTech Lithium" or the "Company")

Laguna Verde CEOL Terms Agreed with Chilean Government

CleanTech Lithium (AIM: CTL, Frankfurt:T2N), an exploration and development company advancing sustainable lithium projects in Chile, is delighted to announce that the Company and the Mining Ministry in Chile have formally agreed the contractual terms on which the Special Lithium Operating Contract ("CEOL") for Laguna Verde is to be awarded to CleanTech Lithium and its minority-party consortium partner. A final ratification step is required by the Comptroller General's Office (the "Comptroller") to ensure the Decree complies with the Constitution and laws of Chile.

Highlights:

·    CleanTech Lithium has agreed via its wholly owned subsidiary, Atacama Salt Lakes SpA ("ASL"), the terms of the CEOL with the Ministry of Mining in Chile.

·    This is a transformational de-risking event for the Company. It provides long-term contractual certainty directly with the Chilean State, underpinning the investment case and accelerating the path to production.

·    The CEOL runs for 40 years with an area of 153km² and covers all aspects of project development: exploration and evaluation, construction, lithium production, and project closure. See appendix for final government defined polygon area which, as a result of local indigenous consultations, now excludes the lake surface area. 

·    All the material economic, commercial and legal terms are substantively consistent with other CEOLs in Chile.

·    The CEOL reaffirms the Company's commitment to deliver meaningful socioeconomic benefit to the Atacama region and alignment with Chile's National Lithium Strategy.

·    Consistent with all other decrees in Chile, a final review is required by the Comptroller to ensure it complies with the Constitution and laws of Chile. The Board is not aware of any reason why the Decree would not be processed and anticipates ratification will take place in Q2 2026.

·    Please watch an interview with CEO Ignacio Mehech discussing the significance of this news: click here to watch

Ignacio Mehech, Chief Executive Officer of CleanTech Lithium, commented: "I am delighted to share this news with our shareholders and wider stakeholders as this is arguably the most significant moment for CleanTech Lithium's flagship project, Laguna Verde. The agreement of the CEOL demonstrates the strong alignment between Laguna Verde and Chile's strategy to expand lithium production responsibly and sustainably, emphasising the Government's confidence in our approach to project development.

"This represents a landmark occasion for the Company; we are one of only a few companies being awarded a CEOL. I would like to personally thank the team and all stakeholders who were involved in this effort and our shareholders for their support during what proved to be a protracted process. We can now move forwards to the next phase of unlocking the full potential of Laguna Verde."

Details:

Having successfully progressed the application filed by ASL on 29 December 2025, the terms of the CEOL have been formally agreed by the parties. With a term of 40 years, the CEOL will start from the date on which the administrative act (the "Decree") issued by the Ministry of Mining approving the contract has been fully processed. For this to happen, the Ministry has sent the Decree to the Comptroller.

Consistent with all other decrees in Chile, a final ratification step is required by the Comptroller to ensure the Decree complies with the Constitution and laws of Chile. The Comptroller may not change the terms agreed in the CEOL and the Board anticipates Comptroller ratification will take place in Q2 2026, as previously reported. Furthermore, the Board is not aware of any reason why the Decree will not be approved.

The CEOL covers all phases of the project: exploration and evaluation, construction, lithium production, and project closure. The Company also notes that all the material economic, commercial, and legal terms are substantively consistent with other CEOLs awarded in Chile.

As part of the CEOL, the Company commits to delivering meaningful socioeconomic impact to the region and is strongly aligned with Chile's National Lithium Strategy. CTL has already established partnerships with local indigenous communities and regional universities. With the Decree submitted for ratification, the Company will now finalise its Pre-Feasibility Study ("PFS"), publish the results and enter the next phase of the Project´s commercial development which includes the introduction of a strategic partner.

The Laguna Verde Project

CleanTech Lithium has undertaken extensive exploration and development activities at Laguna Verde since 2021, focused entirely on the subsurface brine aquifer in the basin. From the multiple drilling programmes, the Company has encountered average grades of lithium of 175mg/L and recorded up to 409mg/L at depth. The Project is considered highly commercial with a previously announced (10 November 2025) JORC compliant resource estimate of 1.9 million tonnes of lithium carbonate equivalent ("LCE") (see note) equating to a multi-decade opportunity. The Company is proposing to use Direct Lithium Extraction ("DLE") methods to efficiently extract lithium without the use of evaporation ponds. CleanTech Lithium aims to make the Laguna Verde Project a model for low-cost, low-impact lithium production in Chile. (Note: the Resource Statement set out above may be subject to revision in due course in the light of the final polygon.)

The information communicated within this announcement is deemed to constitute inside information as stipulated under the Market Abuse Regulations (EU) No 596/2014 which is part of UK law by virtue of the European Union (Withdrawal) Act 2018. Upon publication of this announcement, this inside information is now considered to be in the public domain. The person who arranged for the release of this announcement on behalf of the Company was Steve Kesler, Director and Chairman.

Appendix

Figure 1: The final Government defined polygon area for Laguna Verde.

"Zona Exclusión" represents the lake surface (updated as a result of local indigenous consultations).

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Beaumont Cornish Limited ("Beaumont Cornish") is the Company's Nominated Adviser and is authorised and regulated by the FCA. Beaumont Cornish's responsibilities as the Company's Nominated Adviser, including a responsibility to advise and guide the Company on its responsibilities under the AIM Rules for Companies and AIM Rules for Nominated Advisers, are owed solely to the London Stock Exchange. Beaumont Cornish is not acting for and will not be responsible to any other persons for providing protections afforded to customers of Beaumont Cornish nor for advising them in relation to the proposed arrangements described in this announcement or any matter referred to in it.

Notes

CleanTech Lithium (AIM:CTL, Frankfurt:T2N) is an exploration and development company advancing lithium projects in Chile for the clean energy transition. CleanTech Lithium has two key lithium projects in Chile, Laguna Verde and Viento Andino, and exploration stage project in Arenas Blancas (Salar de Atacama), located in the lithium triangle, a leading centre for battery grade lithium production.

CleanTech Lithium is committed to utilising Direct Lithium Extraction ("DLE") with reinjection of spent brine resulting in no aquifer depletion. Direct Lithium Extraction is a transformative technology which removes lithium from brine with higher recoveries, short development lead times and no extensive evaporation pond construction. For more information, please visit: www.ctlithium.com

**ENDS**