Valerie Amos, the UN under- secretary-general for humanitarian affairs, on Friday said that she was deeply frustrated and disappointed that the Geneva II talks concluded earlier in the day without an agreement on humanitarian pauses to bring relief to hundreds of thousands of people blockaded in towns and cities in war-torn Syria.

"She said that more than three million people in Syria are trapped in areas where heavy fighting continues or that are besieged by government or opposition forces," Farhan Haq, the acting deputy UN spokesman, said at a daily news briefing here. " The situation is totally unacceptable."

"She said that the international community has clearly called for immediate action to facilitate safe and unhindered delivery of assistance across the country, but so far, this has not translated into significant progress or action on the ground," Haq said.

"Ms. Amos said that we need urgent action now," he said. " Sieges must be lifted. Ceasefire agreements must be agreed and convoys must be allowed to proceed immediately and safely. Border crossings and roads need to be opened to allow the regular flow of vital aid supplies."

"Those who fail to protect civilians or facilitate assistance are violating international humanitarian law," he said, quoting Amos.

Syrian government and opposition delegates on Friday wrapped up what United Nations officials hope will be just the first stage of talks to end the country's civil war, with the chief mediator reporting no breakthrough to stop the "unspeakable suffering" of the Syrian people, including access for humanitarian aid.

"We haven't made any progress, to speak of," UN-Arab League Joint Special Representative Lakhdar Brahimi told a news conference in Geneva, the site of the eight days of talks, noting that the opposition has agreed to return for a further session on Feb. 10 but that the government delegation said they needed to check back with Damascus first.

"There is absolutely no doubt that the key positions are still very wide apart," he said of the talks, the first time Syrian government and opposition representatives have sat down together in the UN-sponsored bid to help end nearly three years of civil war in which well over 100,000 people have been reportedly killed and nearly 9 million others driven from their homes since the conflict erupted between President Bashar al-Assad and various groups seeking his ouster.

The basis of the talks is full implementation of an action plan adopted in the Geneva Communique of 2012, the first international conference on the conflict, which calls for a transitional government to lead to free and fair elections, but a major issue has been access to humanitarian aid for 1.6 million Syrians, some of whom have been trapped for almost two years without regular food supplies.