Syrian armed opposition groups have rejected the government's demand to lay down their arms and withdraw "unconditionally" from a Damascus-area town by Monday, a spokesperson for the Free Syrian Army (FSA) has told Al Jazeera. 

"We will continue to defend the town and will not stop doing so, no matter what," Abu al-Khair al-Attar, a member of the FSA's negotiating committee, said.

When asked whether the FSA would comply to the government's conditions, al-Attar said: "We will not lay down our weapons as long as the cause that led us to take up arms is still there."

He also said that local opposition factions "will not close the door of negotiations with the regime".  

On Saturday, Syrian government forces blocked the last entrance to Moadamiyah and threatened to launch an offensive on the town if rebel groups, including the FSA, did not "disarm and surrender unconditionally" by Monday, according to the Moadamiyah Media Office. 

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In a press release, the media office said that "the chilling message was delivered during a meeting between the town’s negotiation committee and representatives of the regime". 

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Moadamiyah has been a flashpoint town throughout the Syrian war, which started as an unarmed uprising against President Bashar al-Assad in March 2011. Since then, more than 250,000 people have been killed, according to statistics by the United Nations.

Chemical attacks

The reported threat comes at a time when nearly three years of government-imposed siege have resulted in a grave humanitarian situation. Last week, government forces reportedly killed five residents when they targeted Moadamiyah in a chemical weapons attack, according to activists. 

Speaking to Agence France Press, a Syrian security official dismissed as "baseless" claims that government forces carried out a chemical attack. 

"With the passage cut off, and the lack of medicine after dozens of injuries due to shelling with barrel bombs and toxic gas, people are deeply fearful after the threat," Dani Qabbani, a Moadamiyah-based media activist, told Al Jazeera. 

He said there had been a truce between government forces and opposition groups since March 2014, but that the Syrian military had increasingly violated it in recent months. 

On Saturday, Syrian government helicopters killed three rebels in Moadamiyah when it dropped barrel bombs on the besieged community, according to the UK-based Syrian Observatory for Human Rights. 

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Describing "daily aerial assaults", Qabbani said Moadamiyah was now "100 percent" besieged. 

Sharif Nashashibi, a London-based analyst of Arab political affairs, said that the measure was an attempt by the Syrian government to "consolidate control in the Damascus suburbs".

"These sieges are war crimes. The government is collectively punishing the population of that area because of the presence of 'enemy' fighters," he told Al Jazeera. 

"In the absence of any safe zones or real action on the diplomatic front, the government feels at ease to carry out these sieges, regardless of the immense suffering it causes civilians."

Ghouta, the region where Moadamiyah is located, was first targeted in a chemical weapons attack in August 2013. Leaving hundreds dead, the attack was widely attributed to government forces and pro-Assad militias. 

Follow Patrick Strickland on Twitter: @P_Strickland_ 

Source: Al Jazeera