The most common and most likely answer to this crossword clue is the 9 letter word INTERDICT
I've seen this crossword clue in Independent
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More clues leading to the result INTERDICT
- Court order Bury police overturned on time
- Ban traveller at last in international order
- Ban disheartened the Republican in charge
- Prohibition police backed after Italian club trashed at front
- Prohibition: having three in charge
- Impose ban on criminal tried in court
- Prohibition is international, an order with little right in it
- Censure Bury detective attending court
- Punishment in court’s final ruling very detached
Buddy explains!

The straight part
We know that "Impose ban on" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case impose ban on = interdict.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does INTERDICT mean?
INTERDICT noun- A papal decree prohibiting the administration of the sacraments from a political entity under the power of a single person (e.g., a king or an oligarchy with similar powers). Extreme unction/Anointing of the Sick is excepted.
- An injunction.
- To exclude (someone or somewhere) from participation in church services; to place under a religious interdict.
- To forbid (an action or thing) by formal or legal sanction.
- To forbid (someone) from doing something.
- To impede (an enemy); to interrupt or destroy (enemy communications, supply lines etc).