Russian President Vladimir Putin and U.S. President Donald Trump reaffirmed the importance of the de-escalation areas in Syria as an essential precondition of a political settlement in this country in a joint statement they adopted on the sidelines of the APEC summit in Vietnam.

"President Trump and President Putin confirmed the importance of de-escalation areas as an interim step to reduce violence in Syria, enforce ceasefire agreements, facilitate unhindered humanitarian access, and set the conditions for the ultimate political solution to the conflict," the statement says.

The presidents "reviewed progress on the ceasefire in southwest Syria that was finalized the last time the two presidents met in Hamburg, Germany on July 7, 2017," the document says.

Putin and Trump also welcomed the Memorandum of Principles concluded in Jordan on November 8, 2017.

"This Memorandum reinforces the success of the ceasefire initiative, to include the reduction, and ultimate elimination of foreign forces and foreign fighters from the area to ensure a more sustainable peace," the statement says.

"Monitoring this ceasefire arrangement will continue to take place through the Amman Monitoring Center, with participation by expert teams from the Hashemite Kingdom of Jordan, the Russian Federation, and the United States," it says.

"The two presidents discussed the ongoing need to reduce human suffering in Syria and called on all UN member states to increase their contributions to address these humanitarian needs over the coming months," the statement says.