Owen Paterson has decided to resign as the MP for North Shropshire, saying: "I will remain a public servant but outside the cruel world of politics."
The Conservative former cabinet minister has been at the centre of a furious row after it was recommended he be suspended from the House of Commons for 30 days.
On Wednesday, Conservative MPs - with the encouragement of Prime Minister Boris Johnson - passed a motion in favour of ignoring Mr Paterson's month-long Commons suspension.
As part of the backlash, the government was accused of "corruption" in seeking to overhaul parliament's standards rules in an alleged effort to protect the Tory MP.
Just hours after the government performed a U-turn in the row, Mr Paterson announced his resignation from the House of Commons.
"I have today, after consultation with my family, and with much sadness decided to resign as the MP for North Shropshire," he said.
"The last two years have been an indescribable nightmare for my family and me.
"My integrity, which I hold very dear, has been repeatedly and publicly questioned.
"I maintain that I am totally innocent of what I have been accused of and I acted at all times in the interests of public health and safety.
"I, my family and those closest to me know the same. I am unable to clear my name under the current system.
"Far, far worse than having my honesty questioned was, of course, the suicide of my beloved and wonderful wife, Rose.
"She was everything to my children and me. We miss her everyday and the world will always be grey, sad and ultimately meaningless without her."
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