13 April 2026

First Development Resources plc

('First Development", "FDR" or the "Company')

Selta Project - GAIP survey update

First Development Resources plc (AIM: FDR), the UK-based, Australia-focused exploration company with mineral interests in the Northern Territory  and Western Australia, is pleased to provide an update on the Gradient Array Induced Polarisation ("GAIP") geophysical survey at its Lander West gold target, part of the Company's 100%-owned Selta Project in Australia's Northern Territory.

HIGHLIGHTS

·    GAIP survey has recommenced following temporary suspension, as improved weather conditions allow for safe access and mobilisation back to site.

·    Programme refined to prioritise key prospective areas, following weather-related delays, with the aim of maintaining technical objectives while improving efficiency.

·    One-third of the survey remains outstanding, with completion anticipated within approximately 2 weeks and results intended to inform the next phase of exploration.

Tristan Pottas, Chief Executive Officer of FDR, commented:

"After an unusually heavy rainy season we are pleased to see improving conditions at Selta, allowing our team to safely return to site and resume the GAIP survey at Lander West. While the weather-related delays were unavoidable, they have provided an opportunity to refine the survey scope and focus on the most prospective zones within the target area.

This approach is expected to deliver high-quality geophysical data in a shorter timeframe, supporting our objective of defining robust drill targets. We look forward to completing the programme over the coming weeks and progressing Lander West to the next stage of exploration."

OPERATIONAL UPDATE

The GAIP geophysical survey at the Lander West gold target commenced in early January 2026 and is designed to complement previously completed high-resolution aeromagnetic and radiometric geophysical surveys. The programme aims to enhance the Company's understanding of subsurface geology and structural architecture across the target area, supporting the refinement of potential drill targets.

Unusually heavy seasonal rains resulted in adverse weather conditions across large parts of Central Australia and caused a temporary suspension of the GAIP survey. As a safety precaution in early February, the Company paused field operations and demobilised the survey team, with flooding rendering access tracks impassable, particularly at creek crossings.

The geophysical team has remobilised and the survey has recommenced with a refined scope to focus on the most prospective areas within the Lander West gold target. Approximately 33% of the refined survey area remains to be completed and is anticipated to take around two weeks. The Company expects the refined dataset to provide sufficient geophysical coverage to advance the Lander West gold target to the next phase of exploration.

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ABOUT FIRST DEVELOPMENT RESOURCES

First Development Resources' assets comprise eight granted tenements covering a total area of 2,314.4km². Five of the tenements, comprising three prospective copper-gold projects, are located in Western Australia (WA) while the remaining three tenements, comprising a rare-earth element (REE), uranium, lithium and gold project, are located in the Australia's Northern Territory. All tenements are wholly owned by FDR. The assets are a mixture of drill ready and earlier stage exploration.

The WA Projects include the Company's Wallal Project as well as Ripon Hills and Braeside West Projects situated in the Paterson Province, which is widely regarded as one of the most productive regions in Australia for the discovery of world-class gold-copper deposits, and which is home to several world-class mines and more recent discoveries.

The Selta Project in the Northern Territory is located in an area considered highly prospective for uranium and rare-earth element mineralisation along with base and precious metal mineralisation. Numerous companies are actively exploring within the region.

Beyond the existing portfolio, FDR is actively looking to expand its portfolio through the acquisition of early-stage exploration projects in Australia.