A senior UN humanitarian official says over 200,000 people in Syria have fled their homes in the area around the Islamic State group's de facto capital of Raqqa since April 1.
The figure includes more than 30,000 displaced just this month as US-backed Syrian fighters try to oust the extremists.
Assistant Secretary-General for Humanitarian Affairs Ursula Mueller told the UN Security Council by video from Jordan on Thursday that an estimated 20,000 to 50,000 people remain in Raqqa.
She said the city is encircled and "there is no way for them to get out."
Mueller also said the UN has delivered aid only to a few hard-to-reach areas in Syria and not a single besieged location this month. She blamed the Syrian government, armed groups, insecurity and fighting.