Denmark's premier, whose country is a key player in an international operation to destroy Syria's chemical arsenal, said Wednesday she was "cautiously optimistic" the timetable for doing so will be met.

Helle Thorning-Schmidt was speaking during a meeting with Cypriot President Nicos Anastasiades aboard the Danish frigate HDMS Esbern Snare, which is escorting Syrian chemical weapons shipments and is operating out of nearby Cyprus.

"I am still cautiously optimistic in terms of keeping the timeframe that we have adopted, but it is important that we put some pressure on the Syrians to live up to their part of the bargain, and we are here to fulfil the task," Thorning-Schmidt said.

Under a UN resolution, Syria is to turn over all its chemical weapons for destruction, but Damascus has missed several key deadlines to move material and UN officials have urged it to speed up the process.

Syria says it remains committed to a June 30 deadline to destroy its entire chemical arsenal but that the ongoing civil war is causing delays.

Danish and Norwegian naval vessels are involved in the process of removing the materials from Syria, where they will be transhipped to a US Navy vessel specially fitted with equipment to destroy them at sea.

"We have a mandate, we have the ship, we have the operational tools to fulfil this task and this is why we are here," Thorning-Schmidt said.

"It is very important. We talk about chemical weapons that were used to kill a thousand people, and that is why this task is very, very important."

She was referring to deadly chemical weapons attacks outside Damascus on August 21 that Western governments accused the regime of President Bashar al-Assad of carrying out.