The likes of Liz Truss and Rishi Sunak are being talked about for Boris Johnson 's eventual replacement as the Prime Minister remains under severe pressure.
The government has been rocked in recent months, first by allegations of sleaze regarding now-resigned MP Owen Patterson, before partygate scandals took over.
Leaked emails revealed events took place where people were encouraged to "bring your own booze" and were attended by the PM, who has since claimed he thought it was a work event.
Now, it has also been claimed the former London mayor was thrown a surprise party by his wife Carrie Johnson during the first lockdown on June 19, 2021 - even while there was a strict ban on indoor gatherings.
Events in Whitehall and Downing Street are now under investigation by the Met Police.
There is real anger among MPs and the general public, putting the PM's position under threat
So what happens if he resigns?
Who becomes Prime Minister if the PM resigns?
Johnson can resign as Tory leader, but stay on as PM until a leadership contest determines his successor. This is what Theresa May did in 2019.
As the PM, Johnson must offer his resignation to the Queen before leaving office. There is no set protocol for what happens if a PM does this.
If Boris Johnson resigns as PM before a successor is chosen, the Cabinet Manual says it is "for the party or parties in government to identify who can be chosen as the successor".
This would most likely be Deputy PM Dominic Raab, but it is not guaranteed as there is no clear line of succession.
The Prime Minister (Temporary Replacement) Bill is currently awaiting its second reading.
It aims to "make provision for the carrying out of the functions of the Prime Minister in the event that a Prime Minister, or a person temporarily carrying out the functions of the Prime Minister, is incapacitated; and for connected purposes".
Can the Prime Minister be removed?
Technically, the Queen can sack Johnson, but doing so would only occur in exceptional circumstances and without this, would likely cause a constitutional crisis.
A form of sacking would be his removal as Conservative Party leader through the 1922 Committee.
Fifteen percent of Tory MPs, currently 54, must submit a letter of no-confidence in their leader to committee chair Sir Graham Brady for a leadership vote to be triggered.
All MPs then vote on if they want the leader to stay or go. The PM must win with over 50% of the vote and is exempt from challenges for one whole year if he does so.
If he loses, he would be barred from running in the following leadership contest triggered by the ballot.
What’s the difference between Prime Minister and Deputy Prime Minister?
A Deputy Prime Minister is not always appointed and was last used by David Cameron, who chose Nick Clegg to deputise during the coalition government years from 2010-2015.
It is not a role that is always part of a government's cabinet. Typically, certain ministers were expected to fill in on certain roles and duties while the PM is away or too ill.
The current holder of the role is Dominic Raab, who filled in in 2020 when the PM was recovering from Covid-19 in intensive care.
