League leaders in battle lost, of course (4)

I believe the answer is:

bloc

'league' is the definition.
(group of nations)

'leaders in battle lost of course' is the wordplay.
'leaders in' indicates taking the first letters.
The first letters of 'battle lost of course' is 'BLOC'.

(Other definitions for bloc that I've seen before include "multinational group" , "-- Forsyth, entertainer" , "Political group of nations" , "Group of countries with a shared aim" , "Group with a common policy" .)

I've seen this clue in The Times.

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