Khan has been the MP for Wakefield since 2019.
He said it would be “intolerable” for voters to not be represented.
In a statement posted to Twitter, Khan said: “While legal proceedings are ongoing, I do not believe that it would ordinarily be appropriate to resign.
“However, owing to long delays in the legal process, my constituents have already been without visible parliamentary representation for a year. Even in the best case scenario, anticipated legal proceedings could last many more months.
“I have therefore regrettably come to the conclusion that it is intolerable for constituents to go years without an MP who can amplify their voices in Parliament.”
His resignation will trigger a by-election in the constituency, which had been held by Labour for 87 years before Khan was elected.
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