New premier Haidar al-Abadi had been under heavy international pressure to form an inclusive government that could present a united front against ISIL Takfiri militants, who have seized much of the country's northern parts.
US Secretary of State John Kerry, speaking a few hours before leaving on a mission to solidify the front against ISIL, praised the "new and exclusive" Iraqi cabinet as a "major milestone".
"Now is the time for Iraq's leaders to govern their nation with the same vision and sense of purpose that helped to bring this new government together," he said.
UN Secretary General Ban Ki-moon also welcomed the new government as a "positive step" but urged politicians to quickly choose new defence and interior ministers.
Meanwhile, the new UN human rights chief Prince Zeid Ra'ad Al Hussein said ISIL atrocities promised only a "house of blood" for those living under their rule, while the head of Egypt's prestigious Al-Azhar religious institution also condemned the group.
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