Mitt Romney -- Friend's Ex-Wife Claims Romney LIED to Screw Her in Divorce

We haven't heard back from the Romney campaign office -- however Mitt's attorney was quoted about the Stemberg divorce in Time magazine, saying ... “This is a decades-old divorce case in which Mitt Romney provided testimony as to the value of a company. He has no objection to letting the public see that testimony.”

9:49 AM PT -- A rep for Tom Stemberg also released a statement ... saying, "Over the past several years, the judge in this case has made it very clear that the gag order imposed should not be violated. We have never violated this order and will continue to adhere to the court’s ruling on this case."

Mitt Romney LIED under oath when he testified in the divorce of his good friend and screwed the friend's wife out of a lot of money in the process ... so claims the ex-wife of Staples' founder Tom Stemberg.

Multiple sources connected with the divorce tell TMZ ... during Tom's uber nasty divorce case with ex-wife Maureen, Mitt Romney gave a deposition and testified during the trial that Staples was worth virtually nothing. Romney testified that the company was worth very little and Tom was a dreamer and "the dream continues."

Romney characterized the Staples stock as "overvalued," adding, "I didn't place a great deal of credibility in the forecast of the company's future."

Partly as a result of Romney's testimony, Maureen got relatively little in the divorce, but we're told just weeks after the divorce ended, Romney and Tom went to Goldman Sachs and cashed in THEIR stock for a fortune. Short story -- Romney allegedly lied to help his friend and screw the friend's wife over.

And there's more ... Our sources say years later, Maureen, who suffered from MS and had multiple bouts with cancer, got a visit from one of Tom's guys, who gave her papers informing her that Tom was cancelling her health insurance. Our sources say the irony here is that we're told Tom was working as one of then Governor Mitt Romney's chief health care advisers.

Sources tell us ... Tom also got custody of the couple's one child, making allegations of abuse against Maureen. And get this ... in the mid-90s, after the divorce, Tom sent the boy a letter saying, although he loved him, because of issues related to the divorce "it will not be possible for you to be a part of our family for the foreseeable future."