Declared hands with ace, diamonds, holding it back (9)

'declared' is the definition.
The definition and answer can be both to do with communicating as well as being past participle verbs.
Perhaps there's an association between them I don't understand?

'hands with ace diamonds holding it back' is the wordplay.
I cannot quite see how this works, but
'hands' could be 'men' (synonyms) and 'men' is located in the answer.
'ace' could be 'one' (synonyms) and 'one' is present in the answer.
'diamonds' could be 'd' (abbreviation for the card suit diamonds) and 'd' is found in the answer.
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is found in the answer.
A single letter 'i' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?