Iran-aligned Iraqi armed group Kataib Hezbollah warned on Sunday it would resume attacks on US troops in the region if the United States intervenes in the conflict between Israel and Iran.

"We are closely monitoring the movements of the American enemy's army in the region," Kataib Hezbollah Secretary-General Abu Hussein al-Hamidawi said in a statement. "If America intervenes in the war, we will act directly against its interests and bases spread across the region without hesitation."

Founded in the aftermath of the 2003 US-led invasion of Iraq, Kataib Hezbollah is one of the elite Iraqi armed factions closest to Iran. The group, a key pillar of Iran's network of regional proxy forces, has claimed responsibility for dozens of missile and drone attacks targeting Israel and US forces in both Iraq and Syria.

Early last year, Kataib Hezbollah announced the suspension of all its military operations against US troops in the region in response to efforts by the Iraqi government.

Kataib Hezbollah is part of a coalition of Iran-aligned groups known collectively as the "Axis of Resistance" — an umbrella of hardline Shiite armed factions that have claimed more than 150 attacks on US forces in Iraq and Syria since the onset of the Gaza war about 20 months ago.

Iraq, a rare ally of both Washington and Tehran, is striving to avoid upsetting its fragile stability while focusing on rebuilding after years of conflict.