09 June 2026

Aterian Plc
("Aterian" or the "Company" or the "Group")

Supply Agreement Supports Trading Growth

Aterian plc (LSE: ATN), the African-focused critical minerals exploration, development and trading company, is pleased to announce that its wholly owned Rwanda subsidiary, Eastinco Limited ("Eastinco") has entered into a long-term supply agreement ("Agreement" ) with an established Rwanda-based 3Ts producer and exporter to support the expansion of the Company's trading activities in the Republic of Rwanda ("Rwanda").

The Agreement establishes a framework for sourcing and supplying tin, tantalum, and tungsten ("3Ts") concentrates from Rwanda and is expected to provide additional feedstock volumes for Aterian's growing trading operations.

The Agreement represents a further step in Aterian's strategy to build a scalable, cash-generative critical minerals trading platform alongside its exploration and development portfolio across Africa. Management believes the expansion of the trading business has the potential to become an increasingly important contributor to shareholder value as trading volumes continue to grow.

The arrangement aligns with the Group's strategy to expand its footprint within the East African critical minerals supply chain and strengthen relationships with regional producers and processors. The Agreement includes provisions relating to responsible sourcing, traceability and operational collaboration. The Company expects the Agreement to support increasing trading activity over time as supply volumes ramp up in line with operational targets and market demand.

Strengthening the Group's Executive Focus

Executive Chairman, Charles Bray, will assume direct strategic responsibility for oversight and development of the Group's trading activities, reflecting the increasing strategic importance and scale of trading.  CEO Simon Rollason will focus on advancing the Group's exploration portfolio activities across Morocco, Botswana, and Rwanda.

The Group's strategy remains focused on developing a diversified critical minerals business that balances exploration upside with scalable, cash-generative trading operations.

Trading operations offer Aterian shareholders

·    reduced dilution risk;

·    internal cash flow generation;

·    an exploration funding source;

·    critical minerals market intelligence;

·    strategic counterparty relationships; and,

·    asset monetisation optionality.

Charles Bray, Executive Chairman of Aterian plc, commented:

"This confidential agreement marks another important step in the expansion of Aterian's trading business in Rwanda and strengthens our access to responsibly sourced strategic minerals, enhancing our ability to increase supply volumes and deepen our participation in regional mineral trading flows.

We believe the market has yet to fully recognise the strategic and financial value emerging within Eastinco's trading platform. We have built a fully compliant, revenue-generating business which offers shareholders tremendous upside potential. The continued growth and development of Eastinco represent an increasingly important component of Aterian's broader strategy to build a diversified critical minerals business that combines exploration upside with cash-generative operating activities. 

I believe now is the appropriate time for me to increase my executive focus on the trading business and support the next stage of Eastinco's development. We continue to scale an exciting trading business model designed to create multiple value drivers for shareholders whilst maintaining capital discipline."

Key Trading Developments

In conjunction with the shift in management strategic focus, Eastinco has implemented several operational initiatives intended to support increased trading volumes and future growth, including:

•     Securing a new warehouse and operational facility in Kicukiro, Rwanda, covering approximately 500 square meters, to increase operational capacity, logistics efficiency and inventory throughput;

•     The appointment of Mr D Kayigire as the local Head of Trading and Director of Eastinco, adding further local operational and commercial leadership capacity;

•     Expanding sourcing relationships and supplier networks to support increasing supply volumes across Eastinco's critical minerals trading activities; and

•     Strengthening the Group's executive focus on the continued expansion of its commodity trading operations.

The new warehouse facility is expected to provide Eastinco with expanded storage, handling and operational capabilities, improving logistics efficiency and supporting increasing commodity throughput as trading activities continue to scale, with this Agreement anticipated to potentially increase targeted trading revenues to the Group by 50% before the year-end.

Mr Kayigire's appointment as Head of Trading reflects the Group's continued investment in local operational capability and management infrastructure. He brings senior-level experience in trading, responsible mineral supply chain management, traceability systems and mineral sector operations in Rwanda, with a background spanning mineral sourcing, supply chain oversight and environmental studies. His experience is expected to support the Company's focus on increasing supply volumes while maintaining high standards of responsible sourcing and traceability. Mr Kayigire will focus on strengthening sourcing networks, supplier relationships and increasing supply volumes as Eastinco continues to expand its trading activities.

Traceability & Responsible Sourcing

The Group remains committed to maintaining high standards of supply chain integrity, responsible sourcing and mineral traceability through rigorous due diligence procedures, supplier verification, chain-of-custody controls and ongoing compliance oversight. Management believes strong governance and robust traceability frameworks are becoming increasingly important competitive differentiators as global demand for responsibly sourced critical minerals continues to grow.

- ENDS -

This announcement contains information which, prior to its disclosure, was inside information as stipulated under Regulation 11 of the Market Abuse (Amendment) (EU Exit) Regulations 2019/310 (as amended).

Engage directly with the Aterian PLC management team by asking questions, watching video summaries, and seeing what other shareholders have to say. Please navigate to our interactive investor hub here: https://aterianplc.com/s/fcf8eb

For further information, please visit the Company's website: www.aterianplc.com or contact:

Aterian Plc:

Charles Bray, Executive Chairman - [email protected]

Simon Rollason, Director - [email protected]

Financial Adviser and Joint Broker:

AlbR Capital Limited

David Coffman / Dan Harris

Colin Rowbury

Tel: +44 (0)207 7469 0930

Joint Broker:

SP Angel Corporate Finance LLP

Ewan Leggat / Devik Mehta

Tel: +44 20 3470 0470

Financial PR:

Bald Voodoo - [email protected]

Ben Kilbey
Tel: +44 (0)7811 209 344

Notes to Editors:

About Aterian plc

www.aterianplc.com

Aterian plc is an LSE-listed exploration and development company with a diversified African portfolio of critical metals projects.

Aterian plc is actively seeking to acquire and develop new critical metal resources to strengthen its existing asset base while supporting ethical and sustainable supply chains as the world transitions to a sustainable, renewable future. The supply of these metals is vital for developing the renewable energy, automotive, and electronic manufacturing sectors, which are increasingly important in reducing carbon emissions and meeting global climate ambitions.

Aterian has a portfolio of multiple copper-silver (+gold) and base-metal projects in Morocco. Aterian holds a 90% interest in Atlantis Metals, a private Botswana-registered company holding eleven mineral prospecting licences for copper-silver in the world-renowned Kalahari Copperbelt and three for lithium and salt brine exploration in the Makgadikgadi Pans region. The Company also holds an exploration licence in southern Rwanda, where it is evaluating the tantalum and niobium opportunity, in addition to further exploring for pegmatite-hosted lithium.

The Company's strategy is to seek new exploration and production opportunities across the African continent and to develop new sources of critical mineral assets for exploration, development, and trading.