Stops to get ice (6)

I believe the answer is:

blocks

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'stops' is the definition.
(I know this)

I don't understand how the rest of the clue works.

(Other definitions for blocks that I've seen before include "Three-dimensional shapes with six sides" , "Impedes" , "Prevents the movement of, gets in way" .)

I've seen this clue in the Evening Standard.

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