Angela Kane, Ban Ki-moon's Under Secretary General, has been sent to Damascus to negotiate with Syrian authorities to allow the United Nations access to investigate yesterday's alleged chemical attack.
Angela Kane previously negotiated with the regime for greater access for UN inspectors, earlier in the conflict.
In a statement, the UN said:
The Secretary-General believed that the incidents reported yesterday need to be investigated without delay.
The Secretary-General now calls for the Mission, presently in Damascus, to be granted permission and access to swiftly investigate the incident which occurred on the morning of August 21, 2013.
A formal request is being sent by the United Nations to the Government of Syria in this regard. He expects to receive a positive response without delay.
More top news
The beleaguered Labour Party leader is clinging onto power in the face of as many as 150 MPs voting to remove him from the top job today.
Mr Osborne said he is "not the person to provide the unity my party needs".
Actress Lena Dunham has criticised Kanye West's "disturbing" new music video for depicting a host of naked celebrities in bed together.