US Secretary of State John Kerry on Saturday hailed a resolution adopted by the UN Security Council demanding humanitarian aid access in Syria, calling for its "full implementation" with actions.

"This is a resolution of concrete steps to answer the worst humanitarian crisis in the world today," the top American envoy said in a statement. "This could be a hinge-point in the tortured three years of a Syria crisis bereft of hope."

The resolution adopted unanimously by the Security Council on Saturday demands all parties, in particular the Syrian authorities, "promptly allow rapid, safe and unhindered humanitarian access for UN humanitarian agencies and their implementing partners, including across conflict lines and across borders, in order to ensure that humanitarian assistance reaches people in need through the most direct routes."

"This overdue resolution, if fully implemented, will ensure humanitarian aid reaches people in Syria whose very lives depend on it," Kerry said. "This is all about saving innocent lives and relieving the burden on Syria's neighboring countries."

According to UN figures, more than 100,000 people have been killed since the conflict in Syria erupted in March 2011. About 8 million have been driven from their homes in the war-torn country, with more than 2 million of them seeking refuge in neighboring countries.

"Resolutions demanding access mean little without full implementation," Kerry said. "The test is whether the words of the Security Council are matched with the life-saving actions the Syrian people so desperately and urgently need."

As the second-round negotiations of the Geneva II international conference on Syria concluded last week without tangible results, and the Syrian government and opposition could not agree on a date for the next round of talks, US President Barack Obama had pledged to take "some immediate steps" to help the humanitarian situation in Syria and "some intermediate steps" to apply more pressure on the Syrian government.