Ban Ki-moon
Ban Ki-moonReuters

UN Secretary-General Ban Ki-moon on Monday again asked the Security Council to formally request that the International Criminal Court (ICC) begin investigations of war crimes in Syria.

Such a request was blocked in 2014 by Russia and China, which have veto powers and have five times vetoed resolutions on Syria, but Ban said the council should try again.

"I ask and urge the Security Council to bring this matter to the ICC. I am urging them again," Ban told reporters, according to the AFP news agency.

Describing the situation in Aleppo as "heartbreaking," Ban said he was disappointed that the council failed to take action during a meeting on Saturday when two resolutions were defeated.

Russia vetoed a French-drafted text demanding an end to the aerial bombardment of Aleppo and to military flights over the city while a second measure drafted by Moscow urging a ceasefire was defeated.

"There is no such time to debate and disagree," Ban said, adding that it was "evidently clear" that the council must "work to protect human lives."

The 15-member council has the authority to refer a country to the Hague-based ICC for war crimes investigations as it has done for Libya and Sudan's troubled Darfur region.

In May 2014, France presented a draft resolution calling for war crimes to be investigated in Syria, but the measure was defeated when Russia and China used their veto power to block the request.

French Ambassador Francois Delattre did not rule out another attempt, but said diplomats need to be "creative" about how to get the ICC involved in a war crimes probe in Syria.

"When you bomb hospitals, when you bomb schools, when you kill children, if these are not war crimes then frankly then I don't know what war crimes are," said Delattre.

Syria announced an all-out offensive for Aleppo on September 22, shortly after a ceasefire brokered by the United States and Russia fell apart.

Last week, however, the Syrian military said it would "reduce" air strikes on rebel territory to allow civilians in the city to flee.

The Security Council remains deeply divided over Syria between Russia, which is offering military support to President Bashar Al-Assad, and Western powers backing rebel forces.

More than 300,000 people have died in the five-year conflict in Syria.

AFP contributed to this report.