The first images have been released of the proposed temporary home for MPs during restoration work in Parliament.
Architects plan to recreate the current chamber of the House of Commons, including the green benches on which MPs sit, at a new venue in Westminster.
The planned move to Richmond House, the home to the Department of Health, will not happen until 2025 at the earliest.
Legislation is being published to create a Olympics-style delivery body to oversee Parliament’s refurbishment.
MPs voted last year to leave the Palace of Westminster, which houses the Commons and the Lords, while the multi-billion pound repairs take place.
Commons leader Andrea Leadsom said the bill would ensure building works deliver “the best possible value for taxpayers’ money”.
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She said the fire that engulfed Notre Dame last month had underlined the importance of preserving historic buildings.
“The Palace of Westminster, recognised the world over as a symbol of democracy, must be restored for future generations,” she added.
Under the plans, a delivery body made up of MPs, peers and external experts will act as a client for restoration works on behalf of Parliament.
It will oversee the delivery of the refurbishments by a separate authority, similar to the one created to build infrastructure for the 2012 London Olympic Games.
A cross-party committee which scrutinised a draft of the bill said it was “disappointing” the government had rejected its recommendation for MPs and peers sitting on the body to be elected by Parliament, not put forward by party leaders.
Conservative MP Dame Caroline Spelman, who chairs the committee, said electing members would “would ensure their independence and that they were answerable to their colleagues in Parliament”.
What future works are planned?
The work is expected to include replacing old cabling, installing a new sewage system and improving disabled access to the estate.
Both the Commons and Lords agreed in early 2018 that the most cost-effective way to carry out the upgrades would be for them to move out whilst the works are being done.
A detailed design brief and budget will need to be signed off by Parliament, with more exact cost known once the new body has made its business case.
In 2015 the Independent Options Appraisal estimated the one-phase programme would cost between £3.52bn and £3.87bn, at 2014 prices.
The delivery authority will be responsible for drawing up full details of plans and costs, which will have to be approved by MPs.
The legislation will also create a new committee to scrutinise the sponsor body’s spending plans alongside the Treasury.
The Commons is expected to move temporarily into nearby Richmond House while the works are going on.
Later, parliamentary authorities will reveal plans for the refurbishment of the building, including a temporary chamber for debates.
They will also announce plans to develop seven other historic buildings on Parliament’s Northern Estate.
Former Clerk of the Commons Lord Lisvane said it was “a matter of time” before something happened to the parliamentary estate.
“I’m afraid there has been a certain amount of foot-dragging and my message now would be emphatically, crack on with it,” he told the BBC.
Labour’s Meg Hillier, who chairs the the Public Accounts Committee, said a final cost for the works would only be known once MPs move out but would be “many billions” of pounds.
She added that it is hard to be “absolutely sure” when MPs would move back in once the repairs begin.