The US Defense Innovation Unit (DIU) is seeking technology to counter unmanned underwater vehicle threats. UK companies can apply, with solutions assessed by jHub — for potential UK defence use.
The US DIU has launched a Commercial Solutions Opening (CSO) which is a fast, flexible route for companies to pitch technology directly to government. The programme, called REEF (Robotic Exclusion and Engagement Framework), seeks technology to counter the threat of unmanned underwater vehicles (UUVs).
The deadline to submit ideas to the challenge is 3 April 2026.
UUVs, such as autonomous submarines, are increasingly being used by adversary actors to threaten ports, harbours, naval forces, and other critical maritime infrastructure.
Current approaches to countering this threat are often expensive and limited in number. The REEF programme is looking for a coherent, scalable system that covers both detection and defeat UUVs, giving end users the tools they need to act quickly and decisively, while keeping a human in the loop at every stage.
UK involvement in this process reflects the close innovation partnership between the UK and US. UKDI and the US DIU recently signed a Memorandum of Understanding (MOU), formalising their commitment to collaborate on exactly these kinds of cutting-edge challenges. REEF is an early example of that partnership in action. It also demonstrates how UKDI is working with allied innovation teams to identify cutting-edge capability that could strengthen UK defence.
UKDI initiated the project, which is being delivered through Cyber and Specialist Operations Command’s Innovation team, the jHub - who will assess submissions for potential UK defence applications.
The U.S. and UK are seeking technology across four areas:
The competition is looking for sensors and systems that can detect, track, and classify underwater threats in challenging environments, reducing false alarms and distinguishing genuine threats from natural contacts.
On the defeat side, non-kinetic solutions such as deployable barriers, nets, or acoustic systems are preferred, though kinetic options will be considered. Decoy systems are also of high interest.
Underpinning everything, the programme seeks secure, near real-time data transmission and an intuitive command and control system that brings sensor data together into a clear operating picture.
The competition is run and managed by the US DIU. The deadline to submit ideas to the challenge is 3 April 2026.
Full details, submission guidance, and timelines are available at the US DIU website.
https://www.gov.uk/government/news/uk-and-us-seek-solutions-to-counter-underwater-drone-threat