UNITED NATIONS -- An international investigative mechanism for crimes committed in the Syrian civil war is gathering large volumes of information, said head of the mechanism on Tuesday.

Operational since May 2018, the International, Impartial and Independent Mechanism (IIIM) has collected over 1 million records and the collection is growing exponentially with the ingestion of whole databases, Catherine Marchi-Uhel, head of the mechanism, told the UN General Assembly in her annual speech.

"We see opportunities to reserve new resources for filling in gaps in the existing evidence through targeted investigations."

The IIIM model can assist domestic criminal justice actors in their effort to prosecute individuals for crimes committed in the Syrian civil war, by providing them with evidence, structural analysis, expertise and peer-to-peer engagement, she said.

Reflecting the potential of an integrated approach between international and national actors, the mechanism has received a total of 23 requests for assistance from war crimes units and national judiciaries, said Marchi-Uhel, noting that the rate of receipt will increase.

She saw the IIIM model as an opportunity to help address some of the weaknesses in the existing international criminal law framework. "We see opportunities to bridge the divide between, on the one hand, fact-finding missions as well as commissions of inquiry and, on the other hand, international courts and tribunals. We see opportunities to aggregate and centralize large volumes of information and evidence from civil society, international organizations, states and individuals and to vet, process and analyze it according to international criminal law standards and with high-tech capabilities."

She cautioned that the work of the mechanism will take a long time and asked for international support.

"To gather and prepare the evidence that proves guilt beyond a reasonable doubt, especially for complex large-scale crimes, takes time."

Following the commencement of the process by the UN secretary-general to include the IIIM in the 2020 UN regular budget, sustainable funding will be ensured in the years to come, she said, calling on states to continue supporting the transition of the mechanism to the regular budget.

The mechanism is a novel model with significant potential, she said.

The IIIM was established by the UN General Assembly in December 2016 mechanism to assist in the investigation and prosecution of persons responsible for the most serious crimes under international law committed in Syria since March 2011.

A Joint Investigative Mechanism endorsed by the UN Security Council to determine the perpetrators of chemical weapons use in Syria ceased to be in November 2017 after Russia vetoed the extension of its mandate.