The most common and most likely answer to this crossword clue is the 9 letter word BALTIMORE
I've seen this crossword clue in Independent
B
A
L
T
I
M
O
R
E
More clues leading to the result BALTIMORE
- Indian cooking style needs extra American port
- Maryland port using Indian food to a greater extent
- Indian customs mainly seen in American city
- Two soldiers carrying medical officer in a US city.
- Indian food with extra port in America
- Indian dish served with extra in US city
- City where Oliver wanted this curry first
- Flier’s request for seconds in curry house?
- . US city's evil grip over Asian island
- Two boys go through tunnel in the city...
Buddy explains!

The straight part
We know that "US city." is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case us city. = baltimore.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.