The big redevelopment plan will allow MPs to decamp to the cluster of buildings, ahead of restoration and renewal of the Palace of Westminster.

This will require Richmond House, the former home of the Department of Health in Whitehall, to be rebuilt to allow it to become a temporary House of Commons.

There will also be extensive upgrades to buildings in the Northern Estate to create a new secure campus.

Lendlease has secured the job to rebuild Richmond House, while Wates has the task of upgrading the rest of the Northern Estate.

The estimated construction cost of the Northern Estate Programme plan is £600m-£800m. It is expected that around half of this cost would relate to the Richmond House rebuild.

But allowing for higher contingencies for a heritage building project of this scale, VAT and inflation, the overall budget cost range for the entire Northern Estate Programme is expected to be set at £1.4bn to £1.6bn.