The strikes, which took place late Friday and resulted in 45 fatalities, were a response to a drone assault linked to Tehran-aligned militants on a US base in Jordan.

Although the US avoided hitting inside Iran, efforts were made to prevent civilian casualties; however, reports of civilian deaths emerged from both Iraqi and Syrian officials.

Iraq and Syria, along with Tehran, accused the US of destabilizing the region amidst already heightened tensions including the Israel-Hamas conflict in Gaza.

A US National Security Council spokesperson stated that aircraft targeted 85 locations, carefully chosen to protect civilians. Despite this, Iraq reported civilian casualties among the 16 dead in the western part of the country, a claim that conflicted with a monitoring group's report that all 29 individuals killed in Syria were militants.

The Iraqi government reacted by declaring three days of mourning and lodging a formal protest, while Iran and Hamas criticized the US actions as increasing regional unrest.

The UN Security Council plans to discuss the strikes, as requested by Russia due to concerns over regional peace and security. Syrian official reports and the Syrian Observatory for Human Rights provided conflicting accounts of civilian casualties.

The Syrian military demanded a US troop withdrawal, criticizing their presence in the region. Despite the US's claim of notifying Iraq prior to the strikes, the Iraqi government dismissed this as misleading.

The US maintains a presence of 900 troops in Syria and 2,500 in Iraq to combat the Daesh terrorist group, with the latter stationed by Iraq's invitation.

However, the legality of their presence in Syria, where they are outside government control, has been contested. Analysts question the effectiveness of the strikes as a deterrent, while a pro-Iran Iraqi group vowed retaliation.

Since mid-October, over 165 attacks on US and coalition troops have been reported, with recent fatalities marking the first American deaths from hostility in the latest violence.