The United Nations is in talks with Turkey to boost cross-border aid flows into northwest Syria and allow more evacuations of those in urgent need of medical help, such as babies in incubators, as shelling draws closer.

More than three million people are trapped in northwest Syria between the Turkish border and advancing Syrian government forces, who are trying to seize back control of the last large opposition-held province of Idlib.

Mark Cutts, UN deputy regional humanitarian coordinator for the Syria crisis, said fighting was now coming “dangerously close to the area where more than a million are living in tents and makeshift shelters.”

“We have been talking with the Turkish authorities about ways of increasing the capacity of aid crossing at the border from Turkey into northwest Syria,” Cutts told reporters.

About 50 trucks daily are crossing the bigger of two authorized Turkish border crossings, Bab al-Hawa, and the UN humanitarian agency OCHA wants to increase this to 100.

“So the aid is flowing, there is a big aid operation, but the reality is that it is simply not enough. We are barely able to meet the needs of people for the most urgent food rations and tents and blankets and winter items,” he added.

Cutts shared with Reuters a message from a medical worker in the Sarmada children’s hospital near the border asking advice on whether to evacuate about 80 babies and infants, including some in incubators and intensive care units.

“With shelling coming close to that area, many of the staff felt they needed to evacuate the hospital but... there was nowhere to evacuate those babies and those infants to,” he said.

Turkey allows some “humanitarian cases” to be sent there for treatment and arrangements could be made for more, Cutts said.

OCHA says 77 medical facilities have been forced to suspend their activities in northwest Syria since Dec. 1. Some were hit by air strikes. Cutts confirmed that a warehouse had been looted last week and said another had been bombed recently.

In January, the UN Security Council allowed a cross-border aid operation to continue from Turkey but closed crossing points from Iraq and Jordan due to opposition from Russia and China.

Cutts said he was “extremely concerned” about the continuation of that cross-border aid after June.

Turkey is already hosting 3.7 million Syrian refugees. It says it cannot take more and was hoping to create a “safe zone” along the border to resettle them but the renewed spike in violence has endangered that plan.

The current wave of displacement is the worst in Syria’s nine-year conflict, with nearly a million people uprooted since December. More than half of them are children.