Three soldiers—two American, one British—were killed, and up to 12 others injured, on Wednesday in a rocket strike against Camp Taji, located north of the capital, Baghdad.
The UN mission, known as UNAMI, issued a statement on Thursday condemning the attack.
“These ongoing attacks are a clear and substantial threat to the country, and the risk of rogue action by armed groups remains a constant concern”, it said.
“Beyond the immediate security threat, this also takes critical political attention away from urgent unfinished domestic business. The last thing Iraq needs is to serve as an arena for vendettas and external battles.”
Tensions have been high in the region since the start of the year following the killing of a top Iranian general in Baghdad, in a US airstrike.
International media reported that some 26 Iraqi forces serving in Syria were killed in an airstrike on Thursday. So far, no one has claimed responsibility.
UNAMI stated that “maximum restraint on all sides is the only way forward”, adding “the Government of Iraq must exercise its full powers to hold perpetrators accountable and prevent future attacks”.