Undiplomatic (adjective)

Not characterized by tact and discretion in dealing with others; lacking diplomacy.

Origin:

From un- (not) + diplomatic (characterized by tact and discretion in dealing with others).

Examples:

1. His undiplomatic behavior caused a diplomatic incident.
2. She was undiplomatic in her dealings with the other countries.
3. His undiplomatic remarks caused an international scandal.
4. The ambassador's undiplomatic actions were not acceptable.
5. Her undiplomatic attitude caused her to be disliked by her colleagues.