Britney Spears has decided to take dramatic action in her ongoing feud with Jamie Lynn Spears. As Entertainment Tonight reports, Jamie Lynn received a notice sent on behalf of Britney's lawyer, stating that talking poorly about her sister in relation to her memoir is to cease and desist at once.

Britney's lawyer addresses "outrageous" claims

Britney's grievances against Jamie Lynn's new book, Things I Should Have Said, first came to light last week. After watching Jamie Lynn promote it on television, Britney tweeted about how upset she was to be brought up in conversation. Despite Jamie Lynn's attempt to diffuse the drama with a social media post of her own, Britney has continued to speak out against her, now escalating things to the next level.

The letter Britney's lawyer Mathew S. Rosengart sent to Jamie Lynn calls her statements against the star "misleading" and "outrageous," saying that Spears and her fanbase alike "were shocked to see how you have exploited her for monetary gain." It also mentioned how Britney "will no longer be bullied" after the termination of her years-long conservatorship, which came to an end in November.

Jamie Lynn Spears attends the 50th annual CMA Awards on November 2, 2016.

Rosengart then called Jamie Lynn's treatment of Britney's character "potentially unlawful and defamatory." The letter warned that Britney "will be forced to consider and take all appropriate legal action" against her if she does not stop negatively discussing her while promoting her book, which she has said Britney is not the focus of. And seeing as Britney is now able to handle her own legal affairs, the warning is one Jamie Lynn should heed!