Iraq's UN envoy said Friday there was no evidence that the Islamic State group had used chemical weapons in the battle for Mosul.

Ambassador Mohamed Alhakim said he conveyed the information to the United Nations after speaking with his government in Baghdad on Friday.

"There is really no evidence that Daesh has used this chemical weapon," Alhakim told reporters ahead of a Security Council meeting on Iraq. Daesh is the Arabic acronym for the Islamic State (IS).

The Red Cross had reported that seven people, five of them children, had been hospitalized near Mosul in early March suffering from exposure to a chemical agent. 

The US Defense Department said that IS militants were developing rudimentary chemical weapons such as mustard gas at the University of Mosul. 

Iraqi forces launched an operation to retake west Mosul, the largest population center still held by the jihadists, on February 19.

Alhakim said Iraq had been in contact with The Hague-based Organization for the Prohibition for Chemical Weapons (OPCW), which could dispatch a team of experts in the event of a suspected toxic gas attack.

Following the closed-door Security Council meeting on Iraq, British Ambassador Matthew Rycroft said the Iraqi investigation of the alleged chemical attacks had not been completed and that the council had expressed concern.

"We look forward to the results of Iraq's investigation into those allegations," said Rycroft, who holds the council presidency this month.

source: AFP