Former Vice President Joe Biden escalated his skirmish with Sen. Elizabeth Warren (D-Mass.) over their competing health care plans, writing in an essay Tuesday that she was taking a dangerous my way or the highway approach to the issue.

In a post on Medium , the Democratic presidential hopeful also zeroed in on comments his rival made last week that he was running in the wrong presidential primary and repeating Republican talking points by criticizing her Medicare for All plan. Warrens proposal is bolder and more progressive than Bidens, but also more expensive.

The other day I was accused by one of my opponents of running in the wrong primary. Pretty amazing. On one level, it is kind of funny, Biden wrote.

But at another level these kinds of attacks are a serious problem, he continued. They reflect an angry unyielding viewpoint that has crept into our politics. If someone doesnt agree with you its not just that you disagree that person must be a coward or corrupt or a small thinker.

Biden, who pitches himself as more able to win over moderate voters in crucial swing states than Warren or the other major contenders in the Democratic race, emphasized throughout the piece that Warrens comment is no way to bring the country together. This is no way for this party to beat Donald Trump in next years presidential election.

Warrens remarks came after Bidens campaign launched an attack on her Medicare for All plan, accusing her campaign of using mathematical gymnastics to hide that its $21 trillion cost would require tax increases on the middle class.

Biden, by contrast, is proposing an expansion of former President Barack Obama s Affordable Care Act and allowing people to keep their private insurance if they want to.

The two will face off over health care and other issues more at a Nov. 20 debate alongside that also will feature at least seven other candidates .