Over 40,000 people have now signed an online petition calling for Tory MP David Ruffley to resign following his caution for domestic assault.
Mr Ruffley announced earlier that he would be stepping down at the 2015 general election, saying the "protracted media debate" about the incident was damaging his constituency party.
The organiser of the petition, Jo Costello, said he should resign immediately, calling it "unthinkable" that he should stay in Parliament until next year.
But Conservative Chief Whip Michael Gove said he was "sorry" that Mr Ruffley had decided to leave Parliament.
""David Ruffley MP has given a huge amount to Parliament both on the Opposition front bench and as an outstanding member of the Treasury Select Committee," the former Education Secretary said.
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