The eight-year framework will run from March 2027, with an initial five-year term and an option to extend to 2035.

It will create a long-term supply chain to deliver everything from building refurbishments and depot fit-outs to major civils, M&E, track, electrification and signalling schemes needed to support existing operations and the introduction of new rolling stock.

The framework will be split into four specialist lots covering internal building fit-outs, access and heavy component movement, integrated multi-disciplinary rail infrastructure projects and specialist design-and-build servicing facilities.

The flagship multi-discipline lot will encompass civil engineering, buildings, permanent way, electrification, high-voltage works, signalling, telecoms, geotechnical engineering, drainage, highways, environmental improvements and mechanical and electrical installations.

Northern said the framework would provide a flexible delivery model capable of handling projects of varying size and complexity.

Contractors will also be expected to drive continuous improvement, innovation and whole-life asset performance across the estate.

Northern has launched an early market engagement exercise ahead of the procurement, with a virtual supplier briefing scheduled for 14 July.

The rail operator is seeking industry feedback on the proposed framework structure, packaging strategy, pricing models, commercial terms and risk allocation before issuing the formal tender.