Sharply worded telegram that forms a barrier (6,4)
I believe the answer is:
barbed wire
'a barrier' is the definition.
(I have seen 'Spiked barrier ' mean 'barbed wire' so perhaps 'barrier' could also mean 'barbed wire')
'sharply worded telegram that' is the wordplay.
I cannot quite see how this works, but
'telegram' could be 'wire' (synonyms) and 'wire' is found in the answer.
The remaining letters 'barbed' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'forms' acts as a link.
Can you help me to learn more?
(Other definitions for barbed wire that I've seen before include "Deterrent fencing" , "warning to keep out" , "something to prevent you moving on!" , "Spiked barrier" , "This sitting on the fence?" .)