Syria has announced it will hold a June 3 presidential election, expected to return Bashar al-Assad to office, as fresh claims emerged of his regime's use of chemical weapons.
Syria's first presidential election -- after constitutional amendments scrapped a referendum system -- is to go ahead despite violence which has killed 150,000 people since March 2011.
Underlining the persistent violence, mortar fire killed two people near the parliament building shortly before the election date was announced.
Speaker Mohammad al-Lahham announced the date in parliament, saying Syrians living outside the country would vote on May 28 and candidates would be able to register from Tuesday until May 1.
Voting would be "free and fair... and under full judicial supervision", he said.
However, the United Nations condemned the announcement, warning it would torpedo a political resolution of the conflict.
"Such elections are incompatible with the letter and spirit of the Geneva communique," UN spokesman Stephane Dujarric said in New York.
He was referring to an agreement on a transition to democracy as the basis for negotiations between the government and the opposition.
The calling of the election came just hours before the United States said that Assad's regime had launched a chemical attack on an opposition village earlier this month.
"We have indications of the use of a toxic industrial chemical, probably chlorine, in Syria this month, in the opposition-dominated village of Kafr Zita," White House spokesman Jay Carney said.
"We are examining allegations that the government was responsible."
Washington called for an investigation. The latest allegation comes as the Organization for the Prohibition of Chemical Weapons and other experts work to remove the Assad regime's chemical stockpiles.
The removal follows an agreement reached after deadly chemical attacks outside Damascus last August that the West blamed on Assad's regime.
Also, French President Francois Hollande said on Sunday that his country had "information" but no proof that Syrian President Bashar al-Assad's regime was still using chemical weapons.
- Election 'farce' -
Assad, who became president after his father Hafez died in 2000 and whose current term ends on July 17, is widely expected to run and win another seven-year mandate despite the conflict.
New election rules require candidates to have lived in Syria for the past decade, effectively preventing key opposition figures in exile from standing for office.
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The opposition, which insists Assad step down and play no role in Syria's future, rejected the election as nothing more than a "farce".
"The Assad regime's announcement today that a 'presidential election' would be held in June should be treated as a farce," said the office of opposition National Coalition leader Ahmad Jarba.
"With vast parts of Syria completely destroyed by Assad's air force, army and militias over the last three years, and with a third of Syria's population displaced internally or in refugee camps in the region, there is no electorate in Syria in a condition to exercise its right to vote."
Much of the international community has also warned Syria against holding the vote, with UN-Arab League peace envoy Lakhdar Brahimi saying it could close the door to any peace negotiations.
Britain on Monday said holding the election during a time of war meant the result "will have no value or credibility".
It remains unclear how Syria's government will organise a vote under the current circumstances, with swathes of the country out of its control.
Syria's conflict began with peaceful protests demanding democratic reform but soon escalated into a civil war after the government launched a massive crackdown on dissent.
- 'What about democracy?' -
Violence continues in many parts of the country, even reaching into the heart of the capital, which has regularly come under mortar fire from opposition fighters on the outskirts.
Syria specialist Fabrice Balanche said the government could only stage the election on 40 percent of the country's territory.
"The election can only be held in the government-held areas, a band of territory stretching from the Jordan border, through Damascus, Hama and Homs," as well as Idlib city, Jisr al-Shughur, half of Aleppo and half of Deir Ezzor, he said.
An activist in Daraya, near Damascus, described the announcement as a new sign of military escalation in the conflict.
"Things are going towards escalation," Amjad Abbar told AFP via the Internet.
On the ground, regime forces were on the offensive on Monday in the central city of Homs, where the Syrian Observatory for Human Rights said clashes were continuing in the Bab Hud and Juret al-Shiyah districts.
Both rebel-held neighbourhoods have been under government siege for nearly two years.
In the northern city of Aleppo, meanwhile, activists said government aircraft dropped barrel bombs on several districts, a day after 52 civilians were killed in air raids in the province.
North of Damascus, a car bomb killed two soldiers at a checkpoint in Mashru Dummar.