The United States says it considers the refugee crisis in Syria to be a global problem.
Speaking in Washington after talks with his German counterpart, Frank-Walter Steinmeier, the US Secretary of State, John Kerry, said he was concerned the Syrian government was creating obstacles to block aid deliveries.
“I want to be clear that the United States considers the refugee crisis to be global. The impact first was felt, obviously, by Jordan and Lebanon and Turkey, and they’ve borne an unbelievable burden in the course of these four and a half, four-plus years of war,” said Kerry.
Kerry also said alleged violations of the break in hostilities will be investigated but added there is no evidence to suggest it will destabilise the fragile peace.
There are reports that up to 1,000 Syrian rebels promised to drop their weapons and join the peace process in a gathering held on Monday in the capital of Darra province.
Both sides accuse the other of continuing hostilities. A break in the fighting was meant to allow peace talks to resume and aid to reach besieged communities.
The cessation deal does not include jihadist groups such as Islamic State and the Nusra Front. Russia, which is backing the Syrian government with air power, has made clear it intends to keep bombing these groups.
Meanwhile, aid trucks carrying non-food items such as blankets have entered Mouadamiya, a suburb of Damascus under siege by government forces.