Video report by ITV News Political Correspondent Romilly Weeks
The House of Commons has been modified to accommodate MPs attending "virtual parliament" as they return to Westminster.
Mr Raab and Sir Keir, who is deputising for recovering Prime Minister Boris Johnson, will both attend the chamber in person, but up to 120 other MPs will be there via video-link.
MPs returning to Parliament on Tuesday approved a motion to allow for "hybrid proceedings", paving the way for the first "virtual" PMQs on Wednesday.
MPs will now be able to contribute to certain parliamentary proceedings via Zoom from Wednesday.
Up to 50 MPs will be allowed in the House of Commons chamber with up to a further 120 contributing remotely to departmental questions, urgent questions and ministerial statements.
Commons Leader Jacob Rees-Mogg said the so-called Hybrid Parliament balances the need for scrutiny with the need to observe social distancing.
He said: "The motion also enables the Speaker to restrict the number of members physically present in the chamber and to ensure that distancing requirements are met."
MPs had been sent for an early Easter recess as coronavirus lockdown measures were imposed on the country.
To ensure social distancing rules were adhered to, only 50 MPs were allowed in the chamber to vote on the motion on Tuesday.
Speaker Sir Lindsay Hoyle urged MPs to "stay at home", however, and said to MPs "let's do it remotely".
Before Tuesday's vote, he told the BBC: "Those that insist on coming – we can have up to 50, I’m not expecting 50 members in at once, far from it, I’m hoping that number is much reduced.”
He stressed there would be “no advantage” for an MP in the chamber over one working remotely.
What will hybrid proceedings look like?
The passed motion allows a maximum of "around 50" MPs into the chamber, under social distancing, at any one time.
Up to 120 MPs will be able to "participate remotely" during hybrid proceedings.
MPs will need to notify the House Service if they want to attend remotely and the list for backbench participation will be drawn at random.
For example, at PMQs, those who want to attend must apply and put forward their questions.
Selected questions will be published in advance.
The speaker - who still plans to Chair proceedings from Westminster, will ensure relevant people are able to attend proceedings relevant to them.
Divisions - when MPs leave the chamber to make votes - will not be covered by the hybrid proceedings.
The Parliamentary Digital Service is working to produce a secure system to facilitate remote divisions, but any change to existing arrangements would have to be agreed by the House.
Any divisions that take place for the time being would be carried out in a way that ensures social distancing, as already announced by the Speaker.
How has the Commons changed?
To prepare the House of Commons for the return of MPs, several contingency measures have been put in place.
A number of large screens have been installed so MPs attending remotely can be seen and heard by those in the chamber.
Tape is on the floor to mark a safe social distance for MPs to stand, and stickers have been placed on benches, showing where people can and cannot sit.
Doors to the chamber will be permanently held open to reduce contact and maintain social distancing for doorkeepers.
Members will also be asked not to pass any notes in the Chamber.
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