Direct Opposites:
* Take away his cup of tea: This directly negates the action of giving him tea.
* Refuse to give him a cup of tea: This expresses a refusal to perform the action.
* Don't give him a cup of tea: This is a more neutral way of saying that the action won't happen.
Opposites in meaning:
* Offer him a different drink: This reverses the specific beverage offered.
* Don't offer him anything to drink: This negates the act of offering any beverage.
* Give him something else: This shifts the focus away from tea.
* Ignore his request for tea: This implies a refusal to acknowledge his desire.
The most accurate opposite depends on the specific context and intended meaning.