Europe can do more in Libya by designating Russian military contractor Wagner Group and calling out Moscow and other countries such as the United Arab Emirates and Egypt that are violating a U.N. arms embargo, a senior U.S. diplomat said on Thursday.

Europeans are “proud” about their naval mission in the Mediterranean Sea, carried out to help enforce the U.N. arms embargo on Libya, but their maritime interdictions have been limited to Turkey, David Schenker, assistant secretary for Near East Affairs at the State Department, told a virtual think-tank event.

“The only interdictions that they (EU) are doing is of Turkish military material that they’re sending to Libya. Nobody is interdicting Russian aircraft, nobody is interdicting Emirati aircraft, nobody is interdicting the Egyptians,” Schenker said.

“They could at least, if they were serious, I think, call them out - call out all parties of the conflict when they violate the arms embargo,” he said.

Libya has descended into chaos after the NATO-backed overthrow of leader Muammar Gaddafi in 2011. Since 2014, it has been split, with an internationally recognized government controlling the capital, Tripoli, and the northwest, while military leader Khalifa Haftar in Benghazi rules the east.

Haftar is supported by the United Arab Emirates, Egypt and Russia, while the government is backed by Turkey. It is a messy battlefield where foreign powers have been pouring in weapons and fighters in violation of the arms embargo.

Washington has increasingly voiced concern about the heavy involvement of Russian mercenaries as well as other external powers and has called for de-escalation, but fighting has persisted.

A U.N. report in May said Russian private military contractor Wagner Group has up to 1,200 people deployed in Libya, strengthening Haftar’s forces.

“There is a lot more that they (Europe) could do. They could, for example, designate the Wagner Group. ... If they aren’t going to take out a more robust role, then this thing is going to drag on,” Schenker said.