On Wednesday, the Russian Defense Ministry said a 48-hour "regime of silence" will be enforced in the Syrian city of Aleppo starting June 16.
"We certainly [have] seen the reports of these new days of silence [in Syria]," Kirby stated. "Even if it is just 48 hours here or a 72 hours there…the violence has been reduced and obviously that’s welcome."
Kirby noted that the United States is continuing to work with Russia on trying to develop mechanisms going forward that can achieve a cessation of hostilities that is better enforced and better sustained over periods of time over the entire country.
"We would like to get beyond a point where we are looking at days of silence in localized areas and get to where the cessation can be actually enforced and enacted nationwide," Kirby explained.
It was too soon to tell, Kirby added, whether the latest localized ceasefire has taken effect in Syria or the degree to which it is being violated.
On Wednesday, US State Secretary John Kerry stated that Russia had to understand that Washington had "very limited" patience left in regard to Syria ceasefire violations.
The Russia-US brokered ceasefire regime in Syria came into force on February 27.