Amentum (AMTM) said Wednesday that UK's nuclear site operator Sellafield has selected its joint venture as a "preferred supplier" for an asset care and asset creation program valued at up to $2.78 billion.

The contract, termed as Projects and Asset Care Execution framework, is aimed at supporting management and retrievals mission of Sellafield's spent nuclear fuel, the company said.

Amentum and its supply chain partners will provide a range of services, including engineering and design, procurement, installation and plant modification and ongoing asset care.

The first lot of the work will be performed by OneAxIoM, a joint venture between Amentum and London-listed Mitie, with Assystem and Mott MacDonald as key supply chain partners.

The initial contract is set to run for nine years, with an optional six-year extension, Amentum added.