Right case for reorganising European Parliament (9)

I believe the answer is:

reichstag

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'european parliament' is the definition.
(I've seen this before)

'right case for reorganising' is the wordplay.
'right case' anagrams to 'REICHSTAG'.
Though, I'm not clear how the anagram is indicated.

Can you help me to learn more?

(Other definitions for reichstag that I've seen before include "Berlin building burnt in 1933" , "European parliament" , "diet in Germany" , "German tourist attraction" , "old German house" .)

I've seen this clue in The Independent.

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