Iraq crisis: Obama says US 'broke Mt Sinjar siege'
President Barack Obama has paid tribute to US forces for an operation in northern Iraq that helped "break a siege" and rescue tens of thousands of displaced people.
Mr Obama said the situation on Mount Sinjar had greatly improved.
Many of those displaced had now left the mountain and further rescue operations were not envisaged, he said.
However, Mr Obama said the US would continue air strikes against the Islamic State (IS) rebel group.
Iraqi and Kurdish forces who were fighting IS would also continue to receive US military assistance, Mr Obama said.
The jihadist militants, formerly known as Isis, seized a large band of territory across northern Iraq and Syria this summer.
The United Nations estimates that 1.2 million Iraqis have been internally displaced by the latest violence.'Modestly hopeful'
Speaking in the US, the president re-emphasised the need for Iraqis to find a political solution to the crisis, describing the prospect of a new and inclusive government, led by Haider al-Abadi, as an "enormous opportunity".
"He still has a challenging task in putting a government together, but we are modestly hopeful that the... situation is moving in the right direction," Mr Obama said.
Mr Abadi, a deputy speaker of parliament, has been asked by the Iraqi president to form a new government.
Current Prime Minister Nouri Maliki, whose coalition won the most seats in April's election, had vowed to contest the move in court, describing it as a violation of the constitution.
However, reports coming out of Baghdad on Thursday evening, and attributed to MPs, said Mr Maliki was to address the nation, announcing he would stand aside in favour of Mr Abadi.
Iraq's Foreign Minister Hoshyar Zebari said Mr Maliki had no choice but to "accept the wishes of the majority of Iraqis".
Mr Zebari, who served under the prime minister until last month, also dismissed fears that Iraq could fall apart, saying the Kurdish leadership had "decided to be part of the new government".
Iraq's military response to a rapid advance by IS has been hampered by political chaos in Baghdad.
On 29 June, the militant group said it had created a caliphate, or Islamic state, stretching from Aleppo in Syria to the province of Diyala in Iraq.
It has declared Iraq a "Level 3 Emergency", its highest ranking of a crisis. The move should enable more resources to be directed in support of humanitarian efforts.
The UN had earlier estimated that tens of thousands of people, mostly from the Christian and Yazidi religious minorities, were besieged on the mountain after being forced to flee their homes.
But US forces sent to Mt Sinjar found fewer people than expected - partly because thousands had left the mountain each night over the past days.
Kurdish officials told the BBC's Frank Gardner that some 150,000 refugees had ended up in the northern city of Dohuk, where the local population was struggling to feed them.
Hamad, a Yazidi who managed to escape with his family, told the BBC that his mother had died during the long journey to Dohuk.
"There was no food. We were exhausted after a lot of walking and climbing high, steep roads," he said, adding that his mother eventually said she could go no further.
"We refused to leave without her. After a few hours of thirst, hunger and exhaustion, she fell and passed away."