UNITED NATIONS, April 18 (Xinhua) -- A United Nations spokesman said Wednesday that some 137,000 people remain displaced from Syria's Afrin district in the Tall Refaat, Nabul, Zahraa and Fafin areas as a result of hostilities and military operations that began on Jan. 20.

"In addition, an estimated 150,000 people remain inside Afrin district, where access to people in need continues to be extremely limited," Stephane Dujarric, spokesman for UN Secretary-General Antonio Guterres, said at the daily news briefing, citing the UN Office for the Coordination of Humanitarian Affairs as saying.

While the UN continues to provide assistance to people displaced from Afrin, the UN does not have direct regular access to the district, and humanitarians operating in the area continue to face access challenges, "largely due to movement restrictions enforced by actors on the ground," he said.

On Tuesday afternoon, UN Emergency Relief Coordinator Mark Lowcock briefed the Security Council, providing updates on Raqqa and other places.

Lowcock said that since Da'esh was forced out of Raqqa in October, nearly 100,000 people have returned to Raqqa city.

However, conditions are not conducive for returns, due to "the high levels of unexploded ordnance and improvised explosive device contamination, widespread and severe infrastructural damage, and a lack of basic services," said the spokesman.