A French ruler accepts my gaining access to e.g., Burgundy (9)

I believe the answer is:

uncorking

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'gaining access to e g burgundy' is the definition.
I can't tell whether this defines the answer.

'a french ruler accepts my' is the wordplay.
'a french ruler' becomes 'unking' (I can't explain this - if you can you should believe this answer much more).
'accepts' means one lot of letters goes inside another.
'my' becomes 'cor' (both are expressions of surprise).
'unking' going around 'cor' is 'UNCORKING'.

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I've seen this clue in The Times.

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