Brown said key objectives that needed to be met for reducing troop numbers included training Iraqi forces, making sure Iraq could push forward with local elections expected this year and also in boosting development in Basra, the country's oil hub.
POLITICAL BREAKTHROUGH
In a political breakthrough, Iraq's main Sunni Arab bloc rejoined the Shi'ite-led government on Saturday after parliament approved its candidates for several vacant ministerial posts.
While it had long been expected, getting the Accordance Front to return after it quit a year ago in a row over power sharing has been seen as vital to healing divisions between majority Shi'ites and minority Sunni Arabs.
Sunni Arabs have little voice in the current cabinet, which is dominated by Shi'ites and ethnic Kurds.
Brown was expected to hail falls in violence in Iraq, particularly in Basra, which was under the control of British troops until they handed over to Iraqi forces last December.
A spokesman for Brown said the prime minister wanted to focus on the "economic element" during his trip and encourage investment in Basra.
Brown is the latest high-profile official to visit Iraq since violence dropped sharply. Turkish Prime Minister Tayyip Erdogan travelled to Baghdad earlier this month and urged the region to help Iraq rebuild after years of war.
Analysts credit an increase in American troop levels and a more assertive stance by Iraq's security forces for reducing violence in Iraq to four-year lows.
Army chief, Jock Stirrup, indicated on Friday that major troop cuts in Iraq, where 176 British soldiers have been killed since 2003, would have to wait until next year.
The unpopularity of the Iraq war was a factor in Brown's predecessor, Tony Blair, stepping down early in June last year.
Iraq has faded as an election issue, but Brown's opinion poll ratings have continued to slump, depressed by faltering growth, rising inflation and sliding house prices.
