The US and Saudi governments affirmed direct talks between the rival Sudanese army and the Rapid Support Forces would begin in Jeddah on Saturday, amid ongoing fighting despite a truce extension.

A joint US-Saudi statement welcomed the "start of pre-negotiation talks" and called for sustained global support to put an end to the fighting.

Fighting between groups supporting the regular army under Sudan's de facto leader Abdel Fattah Al-Burhan and the paramilitary Rapid Support Forces (RSF) under his former deputy Mohammed Hamdan Dagalo has claimed hundreds of lives in just over three weeks.

Sudan's warring sides have announced multiple truces, but none has effectively taken hold.

The army affirmed late Friday it had sent envoys to Saudi Arabia to tackle "details of the truce in the process of being extended" with its paramilitary foes.

Burhan had given his backing to a seven-day ceasefire declared by South Sudan on Wednesday, but early on Friday, the RSF said they were extending by three days a previous truce brokered under US-Saudi mediation.

The United States and Saudi Arabia underlined in their joint statement that other nations and organizations, including the United Kingdom, the United Arab Emirates, the League of Arab States, the African Union, and others had contributed to this weekend's meetings.

On Friday, witnesses in Khartoum reported further airstrikes and explosions, including ones close to the airport.

The fighting intensified despite a threat of sanctions from US President Joe Biden against those responsible for "threatening the peace, security, and stability of Sudan" and "undermining Sudan's democratic transition."

"The violence taking place in Sudan is a tragedy -- and it is a betrayal of the Sudanese people's clear demand for civilian government and a transition to democracy. It must end," Biden claimed.

Children are the biggest victims of the clashes

Armed Fighting Location and Event Data Project revealed that the fighting has claimed the lives of around 700 people so far, most of them in Khartoum and the western Darfur region.

The UN children's agency, UNICEF, warned Friday that "the situation in Sudan has become fatal for a frighteningly large number of children."

According to UNICEF's spokesperson James Elder, 190 children were murdered and 1,700 were injured during the first 11 days of the violence, as per claims from a reliable partner that have not yet been independently verified by the United Nations.

The statistics were gathered from hospitals in Khartoum and Darfur starting on April 15, thus they only include children who really arrived at those facilities, the spokesperson added.

"The reality is likely to be much worse," Elder said.

Aid workers have grappled to get much-needed supplies to areas hit by fighting.

According to the International Medical Corps, at least 18 aid workers have been killed amid the clashes.

The UN Human Rights Council said it would hold a special session next Thursday "to address the human rights impact of the ongoing conflict."

About 450,000 individuals have already fled their homes since the fighting started, including more than 115,000 who have looked for safety in nearby nations.

860,000 refugees are expected to leave the country, according to the UNHCR, which added that $445 million will be needed to help them only until October.

Haines said the clashes had aggravated already dire humanitarian conditions, "raising the specter of massive refugee flows and aid needs in the region."

The UN cautioned that if the fighting resumed, it could raise the already large number of Sudanese imperiled by hunger and malnutrition by as many as 2.5 million.

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