Member of political party spilling the beans but not initially making false claims (9)

I believe the answer is:

libelling

'making false claims' is the definition.

'member of political party spilling the beans but not initially' is the wordplay.
'member of political party' becomes 'lib' (member of the Liberal Democrats).
'spilling the beans' becomes 'telling' (to spill the beans is to reveal something secret).
'but not initially' means to remove the first letter.
'telling' with its initial letter taken away is 'elling'.
'lib'+'elling'='LIBELLING'

I've seen this clue in The Independent.

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