"The ceasefire in Syria has now been in place for six weeks. We are concerned by the recent violations," a communique published on the EU External Action's website quoted Mogherini as saying.
According to the EU top diplomat, it is also necessary to provide access to humanitarian aid in besieged areas.
"Both delegations have the responsibility to make this work and not waste the opportunity to save lives and to put Syria on the road to peace. We expect the Syrian parties and their backers to engage in the process on three key elements that were agreed by all of us in the International Syria Support Group and endorsed by UN Security Council resolutions 2254 and 2268," the EU foreign policy chief said.
A new round of intra-Syrian talks started in Geneva on Wednesday. The previous round of Syrian settlement talks wrapped up on March 24 after 10 days of intense discussions. The round ended in delegates submitting their proposals on how to stop the internal conflict in Syria to de Mistura who then produced a final paper with points of consensus.