The service member, whom the Pentagon confirmed was American, was at least the third killed by enemy fire in Iraq since IS overran swathes of the country in 2014.
President Barack Obama hailed the 2011 withdrawal of American troops from Iraq as a major accomplishment of his presidency, but US forces have been drawn back into combat in the country against IS.
"On May 3, 2016, a coalition service member was killed in northern Iraq as a result of enemy fire," the coalition said in a statement.
US Defence Secretary Ashton Carter said from Germany: "Our thoughts and prayers are with that service member's family."
A coalition military official said on condition of anonymity that the service member was killed at 9:30 am (0630 GMT) by "direct fire" after "enemy forces penetrated" the Kurdish peshmerga forces' line.
Kurdish forces are deployed in Nineveh province, which is centred on Mosul, IS's main hub in the country.
IS attacked the peshmerga in multiple areas of northern Iraq on Tuesday in an attempt to "thwart the plan to liberate Mosul," said Jabbar Yawar, the secretary general of the autonomous Kurdish region's peshmerga ministry.
Tal Asquf is a small Christian town whose population fled when IS overran the region in the summer of 2014.
The United States announced last month that it was deploying additional forces to Iraq, bringing the official total to more than 4,000.
Pentagon spokesman Jeff Davis said the forces would be authorised to advise Iraqis at the battalion and brigade level as opposed to larger divisions, potentially exposing them to greater risks closer to the front lines.
You’ve reached your limit of {{free_limit}} free articles this month.
Subscribe now for unlimited access.
Already subscribed? Log in
Subscribe to read the full story →
Smart Quarterly
₹900
3 Months
₹300/Month
Smart Essential
₹2,700
1 Year
₹225/Month
Super Saver
₹3,900
2 Years
₹162/Month
Renews automatically, cancel anytime
Here’s what’s included in our digital subscription plans
Exclusive premium stories online
Over 30 premium stories daily, handpicked by our editors


Complimentary Access to The New York Times
News, Games, Cooking, Audio, Wirecutter & The Athletic
Business Standard Epaper
Digital replica of our daily newspaper — with options to read, save, and share


Curated Newsletters
Insights on markets, finance, politics, tech, and more delivered to your inbox
Market Analysis & Investment Insights
In-depth market analysis & insights with access to The Smart Investor


Archives
Repository of articles and publications dating back to 1997
Ad-free Reading
Uninterrupted reading experience with no advertisements


Seamless Access Across All Devices
Access Business Standard across devices — mobile, tablet, or PC, via web or app
