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Syria agrees to wider aid efforts, UN says

Thirteen men were shot dead at close range in Syria. Activists claim the killers were government militia. The government blames the rebels. NBC's John Ray reports. Some of the images in this report may be disturbing.

Syria has agreed to allow the United Nations and international agencies to expand humanitarian operations in the country, where at least 1 million people need assistance after 14 months of bloody conflict, a senior U.N. aid official said on Tuesday. 

"This agreement was secured in Damascus with the government there, in writing," John Ging, who chaired the closed-door Syrian Humanitarian Forum, told reporters in Geneva. 

"Freedom of movement, unimpeded access for humanitarian action within Syria, is what it's all about now. The good faith of the (Syrian) government will be tested on this issue today, tomorrow and every day," he said. 

However, the announcement came as Syria labeled 17 diplomats, most of them American or European, as "persona non grata" (unwelcome) in response to a mass expulsion of Syrian envoys by Western capitals last week.

Almost all of those listed have already been recalled by their governments.

"The Syrian Arab Republic still believes in the importance of dialogue based on principles of equality and mutual respect," a ministry statement said. "We hope the countries that initiated these steps will adopt those principles, which would allow relations to return to normal again."

Among those listed were diplomats from former ally Turkey, which has become an outspoken critic of Assad's crackdown and has given haven to army defectors. The foreign ministry said the ambassador and all the staff at Turkey's embassy in Damascus were unwelcome.

Despite the discovery of another atrocity following the recent massacre in Huola, Syrian President Bashar al-Assad showed no sign of relinquishing his power. NBC's Andrea Mitchell reports.

The United States, France, Britain, Canada, Germany, Italy, Spain, Australia, Bulgaria and Switzerland coordinated a move to expel Syrian diplomats in response to a massacre of 108 people in the city of Houla. Nearly half those killed were children.

The BBC reported that US ambassador Robert Ford was called back to Washington in October over fears for his safety, while all British embassy staff were withdrawn in March on security grounds.

France also closed its embassy that month in protest at the "scandalous" repression of dissent by the government, it said.

Syrian security forces are trying to crush a revolt against President Bashar al-Assad's rule.

The London-based Syria Observatory for Human Rights said government forces backed by helicopters clashed on Tuesday with rebels in several towns in the coastal province of Latakia.

"These are the heaviest clashes so far in the area sincethe beginning of the revolution (in March 2011)," Rami Abdelrahman, the head of the Observatory, told Reuters.

Reuters and msnbc.com staff contributed to this report.

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