Significant investment and ongoing maintenance is already taking place across the Parliamentary estate but a more extensive and fundamental programme of works is needed to preserve The Palace for future generations.

The authority is aiming to appoint three long-term strategic partners to deliver the project already billed as Britain’s largest-ever building upgrade.

It is inviting suppliers to its first major early market engagement event in the Palace of Westminster on Monday 16 October to discuss the proposed procurement plan.

1. A Design Services Partner to undertake design services;

2. An Integrator to oversee, manage and integrate the programme; and

3. A Construction Partner to support the development and completion of the design and procure, undertake, and manage the works.

David Goldstone, chief executive of the R&R delivery authority, said: “Over the last year we have focused on the options for delivery and the outcome levels we want to achieve at the Palace, reviewing over 30 options with variant scopes and delivery levels.

“I am pleased to confirm we have now shortlisted just two of these delivery options which have been agreed by our Programme and Client Board and will be presented later this year to the Houses for confirmation as part of the ‘strategic case.

“Having worked up the strategic case we recognise this major programme will need the support of an expert and innovative supply chain, which is why I want to engage with you to ensure we put the right model in place to achieve this.”

He said the plan was to commence procurement for these key long-term partnerships in 2024 before which the authority wanted to test its favoured approach with all interested parties to gain real-time market insights.