U.S. President Barack Obama has said the nomination of Haider al-Abadi as Iraq's prime minister-designate is a "promising step forward."
Speaking from his holiday retreat in Martha's Vineyard, Massachusetts, Obama urged Abadi on August 11 to form a new "inclusive" cabinet "as quickly as possible."
He acknowledged that Iraq had been through "difficult days", and urged the country's political leaders to work together.
Obama's statement markedly left out any mention of the incumbent Prime Minister Nuri al-Maliki.
Speaking in Sydney on August 12, U.S. Secretary of State John Kerry urged Abadi to quickly form an inclusive government.
"We are urging him to form a new cabinet as swiftly as possible and the U.S. stands ready to support a new and inclusive Iraqi government and particularly its fight against ISIL," he said.
The previous day, Iraqi President Fuad Masum asked Abadi to form a new government.
He has 30 days to present a cabinet to parliament for approval.
Maliki, who has refused calls to step down, described Abadi's nomination as a "violation of the constitution."
Maliki has been accused of fueling sectarian violence as the country is battling an Islamist insurgency.
Iraq's premier since 2006, he has been serving in a caretaker capacity since an inconclusive election in April.
UN Secretary-General Ban Ki-moon commended "the forward movement toward government formation" in accordance with Iraq's constitution.
Expressing concerns that heightened political tensions and the current security threat of the Islamic State could deepen Iraq's crisis, the UN chief urged all political parties and their supporters to "remain calm and respect the political process governed by the constitution."
Earlier on August 11, Iraq's highest court appeared to back Maliki's bid for a third term when it ruled that the largest party in parliament should nominate the prime minister.
The National alliance -- which includes Maliki's State of Law party -- is the largest bloc in parliament.
Shi'ite militiamen and security forces loyal to Maliki reportedly were deployed around Baghdad on August 11. There were no reports of violence.
The deadlock over a new government has plunged Iraq into a political crisis at a time when Islamic State (IS) militants are advancing in the north of the country.
The United States has been launching air strikes to support Peshmerga forces battling the Islamic State around Irbil, the regional capital of the autonomous Kurdish region.
On August 11, U.S. fighter jets carried out four air strikes on checkpoints manned by Sunni militants in northwestern Iraq.
The U.S. military said that the strikes outside the town of Sinjar either destroyed or damaged the checkpoints and nearby vehicles that were used by the IS.
Nonetheless, Obama had earlier stressed that there is no American military solution to the crisis.”
"The only lasting solution is for Iraqis to come together and form an inclusive government," he added.
The militants have seized large swaths in northern and western Iraq since they began their offensive in June.
Senior U.S. officials said on August 11 that the United States has begun directly providing weapons to the Kurdish forces.
Following the launch of U.S. air strikes last week, the Peshmerga have started to make some modest gains against the militants.
But on August 11, police said IS fighters had seized the town of Jalawla, 115 kilometers northeast of Baghdad, after driving out Kurdish Peshmerga forces.
President Obama authorized the air strikes to protect U.S. interests and personnel in the region, including at facilities in Irbil, as well as Yazidi and Christian refugees fleeing the militants' advance.
As well as the air strikes, the United States has conducted air drops of essential supplies to Yazidi people stuck in a mountainous area.
On August 12, Kerry said in Sydney that the United States and Australia had agreed to take concerns about the threat posed by jihadist foreign fighters in Syria, Iraq, and elsewhere to the United Nations.
With reporting by Reuters, AP, and AFP