Karen McDougal is suing American Media Inc (AMI), which publishes the National Enquirer, alleging the company took advantage of her “to achieve its own political and financial ends”.
Ms McDougal was paid $150,000 in 2016 for rights to the story of her affair with the business tycoon in 2006 and 2007.
The story never ran but the agreement effectively stopped her from talking to any other publications about what her lawsuit described as a “10-month romantic relationship”.
McDougal says Mr Trump and AMI’s owner David Pecker were close personal friends and the media company “worked secretly” with Mr Trump’s personal “fixer” and Ms McDougal’s then lawyer to “buy her silence”.
The lawsuit says Ms McDougal’s relationship with Mr Trump and the “cover-up” are now “open secrets”, due to recent news reports.
And, while Ms McDougal’s agreement was amended to allow her to respond to “legitimate press inquiries”, AMI was not allowing this.
“…Every time prominent reporters contact Ms McDougal, AMI tells her exactly what she must say – nothing,” the lawsuit adds.
“They threaten her with financial ruin if she does not remain ‘loyal’.
“AMI, meanwhile, feeds those same reporters false information about Ms McDougal, her relationship with Mr Trump, and its own machinations to bind her to silence.”
Mr Trump has denied allegations of sexual misconduct made by more than a dozen women during and after his 2016 presidential campaign.
The lawsuit comes just weeks after porn star Stormy Daniels filed a lawsuit asking a judge to invalidate a non-disclosure agreement preventing her from talking about her affair with Mr Trump.
She described the agreement as “null and void and of no consequence” because Mr Trump did not sign it.
Ms McDougal, a fitness model who was named Playmate of the Year in 1998, had become aware of “the broad effort to silence her and others” and felt she “must speak out”, according to her lawsuit.
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“She will no longer allow AMI to profit from and control her with a fraudulent and illegal contract.
“She therefore asks this court to declare that contract void.”