Formally withdraws (7)
I believe the answer is:
secedes
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">formally withdraws</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for secedes that I've seen before include "Withdraws from an organization" , "Breaks away" , "makes a withdrawal" .)