Announce new king, accepting Charles I as a kind of power (7)
I believe the answer is:
nuclear
'a kind of power' is the definition.
'announce new king accepting charles i' is the wordplay.
I cannot really understand how this works, but
'new' could be 'n' and 'n' is found within the answer.
'king' could be 'lear' (I've seen this before) and 'lear' is found in the answer.
This may be the basis of clue (or it may be nonsense).
'as' is the link.
Can you help me to learn more?
(Other definitions for nuclear that I've seen before include "Possessing atomic weapons" , "basic family" , "Concerning subatomic particles" , "powerful weapons" , "Relating to atomic structure" .)