British Airways (BA) suspended flights over Iraq on Friday as the US launched air strikes against Islamic militants fighting in the north of the country.
A spokesman for Britain's flagship carrier said it was "temporarily suspending our flights over Iraq".
But BA said services that use the route, mainly to Doha and Dubai, would not be cancelled or disrupted because alternative routes would be found.
Willie Walsh, chief executive of BA parent group International Airlines Group, last week pledged to keep flying over Iraq despite mounting concerns over commercial flight paths in the wake of the downing of Malaysia Airlines flight MH17 in eastern Ukraine.
The airline said then it did not believe the conflict in Iraq between government forces and jihadist group Islamic State (IS) posed the same threat to commercial airliners.
But it took its decision to suspend flights after the Federal Aviation Administration banned all US civilian flights over Iraq on Friday, just hours after Washington ordered air strikes on fighters in Kurdistan.
The FAA cited "the potentially hazardous situation created by the armed conflict" between IS militants and Iraqi security forces "and their allies" as the reason for the indefinite ban.