The Food and Drug Administration on Tuesday ordered the two remaining medical device companies selling surgical mesh for the repair of pelvic organ prolapse to stop all sales and distribution in the United States.

It is the most stringent action the F.D.A. has taken in the lengthy legal and medical battles over vaginal mesh, a synthetic product that has been implanted in millions of women to strengthen weakened pelvic muscles that can cause the bladder, the uterus and other organs to sag into the vaginal area.

The agency issued the decision against the two companies, Boston Scientific and Coloplast, at a time when multimillion-dollar verdicts against manufacturers of the devices continue to be awarded or upheld on appeal.

Litigation over pelvic mesh, also called transvaginal mesh, ranks as one of the largest mass tort cases in the nation’s history in terms of claims filed, number of corporate defendants and settlement dollars. Seven medical device manufacturers, including Boston Scientific and Johnson & Johnson, are paying nearly $8 billion to resolve the claims of more than 100,000 women.