The Pentagon said on Wednesday a new US specialised operations force being deployed to Iraq would number about 100, and the majority would not be engaged in raids, Xinhua reported.
"Probably around 100, maybe a little bit less," Steve Warren, spokesman for the US-led military campaign against the Islamic State (IS), said.
He referred to the announcement made by US defense chief Ash Carter on Tuesday that the specialised operations force would "over time" conduct unilateral operations in Iraq and Syria.
"It is really going to be a majority support personnel," said Warren at a Pentagon briefing.
"In fact, really fewer actual trigger-pullers... It's a very small number, a double-digit number," said Warren.
Warren's remarks came one day after Carter outlined here US strategy against the IS at a congressional hearing on Tuesday, during which Carter announced that the Pentagon was sending additional special forces to Iraq.