Rishi Sunak set to be new UK prime minister: Here's what will happen today

Rishi Sunak in UK PM race: In order to be considered for the ballot, hopefuls will need backing of more than 100 MPs.

Rishi Sunak could be hours away from becoming the UK's next prime minister on Monday. The former chancellor and Penny Mordaunt are the only candidates who have formally declared participation in the race while ex-prime minister Boris Johnson who was widely expected to announce his candidacy pulled out of the race late last night.

Rishi Sunak: Britain's Conservative MP Rishi Sunak leaves his campaign headquarters. (Reuters)

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“This is simply not the right time,” Boris Johnson said.

Here's everything that will happen today:

Step 1:

The 1922 Committee of backbench MPs will inform about the candidates who have made it to the ballot. In order to be considered for the ballot, hopefuls will need backing of more than 100 MPs. The name of each candidate's proposer and seconder will be published. Rishi Sunak has over 140 Tory MPs backing him while Penny Mordaunt has the support of 26 MPs.

If only one of them meets the 100 MP threshold, they will automatically become UK's prime minister.

Step 2:

If more than one candidate remains in the race, they will have an opportunity to make their case to MPs. The MPs will then vote in a secret ballot for the next prime minister.

Step 3:

Step 4:

If there are still two candidates in the race after tomorrow, Tory members will vote for their next party leader online.