Celebrate noisily when the Tories move to the right! (7)
I believe the answer is:
roister
'celebrate noisily' is the definition.
(roistering is a kind of celebrating noisily)
'the tories move to the right' is the wordplay.
'move' indicates anagramming the letters.
'to' says to put letters next to each other (I've seen this in other clues).
'the right' becomes 'r' (common abbreviation).
'tories' anagrammed gives 'oister'.
'oister' after 'r' is 'ROISTER'.
'when' is the link.
(Other definitions for roister that I've seen before include "Noisy reveller" , "riot" , "Rioters (anag.)" , "I rest or (anag) - engage in noisy merrymaking" , "bluster" .)