The Federation of Women Lawyers (FIDA) has threatened to prosecute the matter if the Jubilee MP does not issue an apology.
"This is a clear demonstration of elections gender based violence emitted against women. It confirms some of the forms of intimidation that women are taken through when they come out to vie for political positions and strive to maintain public positions.
"We, therefore, demand an immediate apology from Hon Mbai, failure to which we shall take legal action against him. Women should not be cowed from vying, taking up and or maintaining political positions," FIDA Chair Josephine Mong'are said in a press statement.
In a video circulated on social media, the MP was captured calling for the violent act against Governor Ngilu due to her hard stance against President Uhuru Kenyatta.
In a Facebook post on his timeline, Mr Mbai distanced himself from the said video saying that he was being accused unfairly.
"I have always supported Ngilu in my life and I will keep supporting her government," his post read partly.
He went on to describe that he was undeterred in his cause, hinting that he would be vindicated just as the President and his deputy were by the International Criminal Court (ICC).
"Uhuru and Ruto were before the ICC, accused of rape, and they fought through, somebody creates a lie on me talking of rape and they believe this can scare me from my objective," the politician stated.
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