UN aid agencies said on Friday they were rushing supplies to conflict-torn Iraq to help over one million people driven from their homes by fighting.
Donor nations were also holding a closed-door meeting at the UN's European offices in Geneva ahead of an expected fresh funding appeal next week, said Jens Laerke, spokesman for the world body's humanitarian division.
An existing $105-million appeal has garnered just 14 percent of what is needed, he told reporters.
Around 500 000 people have been displaced by fighting in Iraq's western Anbar province, notably the flashpoint city of Fallujah, since the beginning of this year, according to UN figures.
A similar number have fled in the wake the fall of the northern city of Mosul last week, amid a lightning offensive by Sunni jihadists of the Islamic State of Iraq and the Levant (ISIL) against the Shi'a-run government.
And tens of thousands have hit the roads in the eastern province of Diyala, near Baghdad, and the Salah ad-Din region, to the north of the capital.
Earlier this week, UN Secretary-General Ban Ki-moon warned that the surging sectarian conflict threatened to spill over Iraq's borders, interlocking with the civil war raging in neighbouring Syria, where ISIL is also fighting.
Around 300 000 of the people who have fled Mosul have found refuge in Iraq's autonomous Kurdistan region, whose defence forces have vowed to keep out ISIL.
Kurdistan was already under pressure, having taken in the majority of the 200 000 Syrian refugees who have fled to Iraq to escape the war in their homeland.
Most of the Syrian exiles are hosted in local communities, but UN refugee agency spokesman Adrian Edwards said there were fears for the safety of some 5,000 who live in and around Al-Qaem, a camp in Anbar province.
“Many refugees have asked to return to Syria, even though large parts of Syria remain contested,” Edwards told reporters.
He said the United Nations was ramping up its response for the Syrian refugees and Iraqis hit by the conflict alike, rushing in tents, mattresses, blankets and stoves.
“With fighting currently underway in different parts of the country, the displacement crisis could escalate further,” he warned.
The World Food Programme meanwhile said it was bolstering its operations, aiming to feed 435 000 people, and that it feared that fuel shortages caused by the fighting could prove a major hurdle.
“The security of staff and access to affected areas remains a major challenge,” said WFP spokeswoman Elisabeth Byrs.
The World Health Organisation said that Kurdistan authorities had asked for emergency medical aid, because the normal supply route from the Iraqi capital Baghdad had been cut off.
WHO spokeswoman Fadela Chaib cited fears of disease outbreaks among those displaced by the fighting, due to the summer heat, plus a lack of decent water and sanitation. - Sapa-AFP