Several thousand civilians remain trapped by militants on a mountain in northern Iraq and need “life-saving assistance”, the United Nations warns.
Members of the Yazidi sect fled there 10 days ago after fighters from Islamic State (IS) seized the town of Sinjar.
The US has been conducting air strikes to help stem the rapid IS advance in the north of the country.
On Monday, Iraq’s president asked MP Haider al-Abadi to form a new cabinet, snubbing the incumbent PM Nouri Maliki.
Mr Maliki called the nomination a “violation of the constitution”, but on Tuesday ordered security forces not to intervene in the political crisis.
In a statement published on his official website, Mr Maliki said security forces should instead focus on defending the country,
Mr Abadi’s appointment came after months of political infighting, which analysts say is partially to blame for Iraq’s inability to effectively fight the IS threat.
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Desperate Yazidi refugees trapped in Mount Sinjar mobbed an aid helicopter
Politicians had been unable to form a government since April’s parliamentary elections, which were won by Prime Minister Maliki.
IS fighters have seized large swathes of northern Iraq and Syria in recent months, forcing tens of thousands of people from religious minorities to flee their homes.
An estimated 700,000 Yazidis have been displaced since IS militants took Sinjar from Kurdish forces defending the town, the UN says.
Keiran Dwyer, who works for the UN’s office for humanitarian affairs in Irbil, told the BBC that some Yazidis had managed to escape from the north side of the mountain in the last 72 hours and cross the River Tigris into Syria, where they were receiving help.

Thousands of Yazidis ‘still trapped’ on Iraq mountain