Syria's foreign minister on Saturday reportedly said the government in Damascus will allow UN inspectors entry to a site near the country's capital city where an alleged chemical weapons attack was said to have killed hundreds on Wednesday.

Walid Moualem, during a phone call with his Iranian counterpart Mohammad Javad Zarif, categorically denied the Syrian regime's use of chemical weapons, according to official Iranian news agency IRNA.

The "Syrian government will cooperate with the United Nations mission now in Syria to create the conditions for a visit to zones where terrorist groups have carried out attacks with chemical weapons," Moualem was quoted as saying.

"We are currently in the process of discussions with the United Nations mission on preparing this visit," AFP cited the Syrian foreign minister as saying.

Syrian opposition has reported that between 500 and well over 1,000 civilians were killed this week by gas in munitions fired by pro-government forces. The Damascus regime has denied allegations and has suggested rebels may have carried out the latest attack themselves to provoke foreign intervention.

The UN's top disarmament official arrived in Damascus on Saturday to seek access for inspectors to the site of the alleged attack.

Zarif, for his part, condemned what he said was the use of chemical weapons by Syrian opposition forces and stressed that such acts needed to be confronted.

Iranian President Hassan Rouhani said on Saturday for the first time that chemical weapons had killed people in ally Syria and called for the international community to prevent their use.

Rouhani stopped short of saying who he thought had used the arms, but Iran's Foreign Ministry said evidence pointed to rebels fighting Syrian President Bashar Assad.

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