Syrian children buy vegetables at the town of Madaya in the Damascus countryside, Syria, May 18, 2017. (AP/Hassan Ammar)

The U.N. children’s agency warned Friday that a critical funding shortfall is threatening aid to 9 million Syrian children, both in their country and among the refugees in neighboring states.

UNICEF said the $220 million budget gap to its Syria relief programs is the worst it has faced since the start of the conflict, in 2011. It appealed for $1.4 billion in 2017 to provide relief and education to children orphaned, displaced, wounded, or otherwise affected by the Syria war.

A UNICEF statement on Friday said that “without an injection of new funds, some critical and lifesaving activities … are at a serious risk of being cut off, with grave consequences for Syrian children.”

U.N. aid programs have suffered from chronic funding shortfall throughout the Syria crisis. On Tuesday, the U.N.’s refugee agency UNHCR said it had managed to raise only $29 million of the $153 million it had budgeted to meet humanitarian needs in northern Syria, where a U.S.-supported assault on the Islamic State group’s de facto capital Raqqa has displaced more than 100,000 civilians.

Moreover, local obstructionism has severely limited access for the agencies.

The U.N. has been unable to reach any of the 600,000 civilians in Syria it counts as besieged in over 40 days, a top humanitarian official said Thursday.

Jan Egeland blamed the delays on “red tape.” He has previously accused the Syrian government of failing to fulfill its obligations to allow aid access to besieged areas.

Nearly 6 million children are in need in Syria and another 2.5 million require assistance in neighboring countries, according to UNICEF.

In other news, activists reported the government intensified its bombardment against the opposition’s last foothold in Damascus, the Jobar neighborhood.

Opposition activist Anas al-Dimashqi based in nearby Eastern Ghouta said the government was bolstering its forces around the neighborhood with tanks and artillery, and the local rebel faction Faylaq al-Rahman was preparing to weather a new assault against the neighborhood. He said the district was hit 10 times by air strikes on Friday.

An agreement brokered by Russia, Turkey, and Iran in May has calmed the fighting in three of the four areas selected for “de-escalation,” a U.N. investigative commission reported Tuesday.