British leader I sent up, little rascal (3)

I believe the answer is:

imp

I'm a little stuck... Click here to teach me more about this clue!

'little rascal' is the definition.
(imp can mean a misbehaving child)

'british leader i sent up' is the wordplay.
'british leader' becomes 'pm' (PM is an example. I am not sure about the 'british' bit.).
'sent up' says the letters should be written in reverse.
'pm'+'i'='pmi'
'pmi' in reverse letter order is 'IMP'.

Can you help me to learn more?

(Other definitions for imp that I've seen before include "Small demon" , "Young troublemaker" , "A mischievous little devil" , "Mischievous creature" , "Scallywag" .)

I've seen this clue in The Times.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.