A by-election to replace the disgraced Wakefield MP Imran Ahmad Khan is likely to take place in the summer, after the process was officially triggered in Parliament.
The Conservative Party officially's chief whip, Chris Heaton-Harris, issued a writ for the vacant seat in the House of Commons on Tuesday, 17 May.
A writ for Devon's Tiverton and Honiton seat was also issued.
The by-elections have to take place between 21 and 27 working days from the issuing of the writ, suggesting June 23 is the likely date.
The Wakefield contest follows the resignation of ex-Conservative MP Khan after his conviction for sexually assaulting a boy.
The Tiverton and Honiton by-election comes after Neil Parish quit his seat after he admitted watching pornography in Parliament.
Mr Parish, who is a farmer by trade, first said he accidentally viewed one X-rated video when browsing for tractors, before later doing so deliberately in the Commons chamber.
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