Plant secures agreements from French state (9)

I believe the answer is:

louisiana

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'state' is the definition.
(I know that Louisiana is a state)

I don't understand the remainder of the clue.

(Other definitions for louisiana that I've seen before include "American state, capital Baton Rouge" , "US state, capital Baton Rouge" , "IOU a snail over in the US state" , "that's near Mississippi" , "US southern state" .)

I've seen this clue in The Times.

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