Performs a new ascent (6)
I believe the answer is:
enacts
'performs' is the definition.
(I've seen this before)
'a new ascent' is the wordplay.
'a new' is an anagram indicator.
'ascent' with letters rearranged gives 'ENACTS'.
(Other definitions for enacts that I've seen before include "sanctions" , "Passes formally into law" , "Appears" , "Makes into law" , "Establishes by law" .)