African leader once upset UK and America (6)

I believe the answer is:

kaunda

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'african leader' is the definition.
I don't know anything about this answer so I cannot tell whether this works.

'upset uk and america' is the wordplay.
'upset' indicates an anagram.
'america' becomes 'a' (common abbreviation - e.g. in organisation names).
'uk'+'and'='ukand'
'ukand' is an anagram of 'kaund'.
'kaund'+'a'='KAUNDA'

'once' acts as a link.

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I've seen this clue in The Independent.

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