The EU welcomed the establishment of a fact-finding commission in Syria to investigate the recent wave of deadly violence, calling for perpetrators to be "brought to justice".
"We strongly condemn the attacks by pro-Assad militias against security forces," the EU said.
"We also condemn in the strongest terms the horrific crimes committed against civilians, including summary killings, many of which are alleged to have been carried out by armed groups supporting the security forces of the transitional authorities."
A wave of violence erupted last Thursday (6 March), mainly in the Mediterranean heartland of the Alawite minority, that is the deadliest since longtime leader Bashar al-Assad was ousted in December.
At least 1,225 civilians have been killed by security forces and allied groups since March 6, according to the military watchdog Syrian Observatory for Human Rights.
The U.N. human rights office said it had documented "summary executions" that appeared "to have been carried out on religious grounds."
"We welcome the commitments made by the transitional authorities, in particular the establishment of an investigative committee to hold the perpetrators accountable," the EU said.
The bloc called on the authorities to allow international investigators to probe the violence.
"Everything possible must be done to prevent the recurrence of such crimes," it said.
The 27-member bloc also welcomed the agreement to integrate the autonomous Kurdish administration, which has ruled much of the northeast of the country for the past decade, into the national government.
Syria's new authorities, led by interim President Ahmed al-Sharaa, are seeking to disband armed groups and establish government control over the whole of the country.
"This agreement could pave the way to greater stability and a better future for many Syrians. We encourage the parties to work towards its implementation and stand ready to provide support," the EU said.
The international community is closely following developments in Syria as it hopes the country will shake off years of bloodshed after almost 14 years of civil war.
The EU has suspended sanctions on key sectors of the Syrian economy in a bid to help the country rebuild.
However, the bloc has warned that it could re-impose these measures if the new authorities fail to deliver on their promises of an inclusive transition. | BGNES