FACTBOX: Who is Iraqi PM Maliki?

(Reuters) - President George W. Bush's top officials in Iraq will report to Congress next week on security and political progress under Prime Minister Nuri al-Maliki.

Bush is under mounting pressure from opposition Democrats and some senior Republicans to start withdrawing U.S. troops amid growing frustration at Maliki's weak government and the slow pace of national reconciliation.

Here are some key facts on Maliki.

* EARLY LIFE:

-- Born at Hindiya, south of Baghdad, in 1950, he has a masters in Arabic and worked at the Education Ministry before fleeing in 1980 to neighboring Syria and then Iran under sentence of death for his political activism.

* SADDAM OVERTHROWN:

-- He returned after the U.S.-led invasion in 2003 but did not appear in the spotlight like other politicians who were described by some Iraqis as riding in on American tanks.

* PRIME MINISTER:

-- Maliki was thrust to the forefront of Iraqi politics in April 2006 with the image of a tough, Shi'ite Islamist strong enough to weld warring factions together into a national unity government.

* TOUGH JOB

-- Maliki has struggled to hold his government of national unity together. Nearly half the cabinet has quit, including the main Sunni Arab political bloc, which accuses Maliki of sectarianism. Ministers loyal to Shi'ite cleric Moqtada al-Sadr also withdrew after Maliki refused to set a timetable for the withdrawal of U.S. troops from Iraq.

-- Maliki has bristled at growing criticism from U.S. lawmakers, including some such as Democratic presidential hopeful Senator Hillary Clinton, who has called for him to be ousted. Late last month, Maliki told such critics "to come to their senses", adding that there were some American officials "who consider Iraq as if it were one of their villages".

-- Besides the headaches in his own country, he has to tread a fine diplomatic line with neighboring Shi'ite Iran, a country at loggerheads with Washington.

-- Publicly, Maliki does not show any major outward signs of the enormous burden on his shoulders. Some reports suggest he has a strained relationship with the U.S. commander in Iraq, General David Petraeus. By most accounts his ties with Bush are good, and both men speak regularly via videoconference.