Fighting in Syria continues and measures taken by the government to implement a UN-backed peace plan are "clearly insignificant", the UN political-affairs chief says.
Lynn Pascoe's comments came as opposition activists reported shelling in the city of Hama on Monday, a day after UN observers, deployed to monitor the ceasefire requiring both the government and opposition to cease fire, visited the city.,
"The cessation of armed violence remains incomplete," Pascoe told the UN Security Council.
"Too many lives have been lost, human rights violations are still perpetrated with impunity. It is our hope that the deployment of observers will help to stop the killing and consolidate the calm."
A small group of unarmed observers has been in Syria for a week, and the mission will be expanded in the coming weeks. The Security Council has approved the deployment of 300 observers for a three-month period.
Activists said government forces attacked three neighbourhoods, including Arbaeen, on Monday morning. According to some reports, the area was shelled before ground troops entered.
Dozens of people were reportedly killed, and several houses destroyed.
An activist told Al Jazeera that the UN observers had visited the affected areas on Sunday, and that "the regime wanted to take revenge" after residents had taken to the streets to meet them.
"They have arrested so many people across the city," he said. "They havent been arresting people for some time, until today."
Al Jazeera's Anita McNaught has entered Syria with exclusive access to activists delivering medical aid
Meanwhile, state media reported violations on the part of the opposition, saying a colonel and a warrant officer were killed in the same city.
The SANA news agency also said "armed terrorists" had assassinated a physician and an army officer in the southern Deraa province.
Al Jazeera cannot independently verify accounts of violence due to restrictions imposed on international media.
The UN estimates that more than 9,000 people have been killed since the uprising began more than a year ago.
Authorities say more than 2,500 security personnel have been killed.
The UN monitors visited towns around Damascus region on Monday, including Zabadani, where government forces and opposition fighters have clashed repeatedly.
Two observers have set up base in the central city of Homs, scene of some of the most intense violence.
SANA said the observers toured the city's al-Waer neighbourhood on Monday.
'Luxury goods' embargo
In the latest move to pressure President Bashar al-Assad and his allies, the European Union banned the sale of luxury goods and products to Syria that can have military as well as civilian uses.
Catherine Ashton, EU foreign affairs chief, said the EU's 27 foreign ministers approved the new set of sanctions - the 14th in the past year - "because of deep concern about the situation and continuing violence in spite of the ceasefire".
EU experts will work out later precisely which goods will be included in the new embargo. One diplomat said so-called "dual-use" goods can include anything from vehicles to fertilisers and other chemicals.
The only precedent in international relations for the luxury ban is one imposed by the EU in 2007 on North Korea for its nuclear and ballistic missile programs. Officials said this could serve as a model for the same measure against Syria. That ban included foods such as caviar and truffles, high-quality wines and spirits, fashion accessories including
In the US, President Barack Obama also unveiled sanctions on Monday, targeting those who help Syria and Iran track dissidents through mobile phones and computers and said he would keep adding pressure on both governments to prevent mass atrocities.
He said Syra and Iran were monitoring the social media to plot attacks against opposition groups.
"These technologies should be in place to empower citizens, not to repress them," Obama said, announcing new asset freezes and visa restrictions against Syrian and Iranian agencies as well as those helping them access surveillance used to plan violence.