Alert restricts summit of Kyiv? (3-4)

'kyiv?' is the definition.
I can't judge whether this defines the answer.

'alert restricts summit' is the wordplay.
'alert' becomes 'wary' (similar in meaning).
'restricts' means to remove the last letter (I've seen 'restricted' mean this (restricted can mean limited or reduced)).
'summit' becomes 'torn' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'wary' with its final letter taken away is 'war'.
'war'+'torn'='WAR-TORN'

'of' acts as a link.

Can you help me to learn more?