(Adds details on regions)
BRUSSELS, July 29 (Reuters) - ArcelorMittal, the world's largest producer of steel, said improving steel prices and better volumes boosted its results in the second quarter, but remained cautious about 2016 as a whole, keeping its outlook.
Core profit (EBITDA) almost doubled in the second quarter compared to the same period last year to $1.77 billion, well above the $1.57 billion expected in Reuters poll of eight analysts.
The group grew core profit in both mining and steel production in all of the regions except for Brazil, where selling prices were down by a quarter compared to last year and the economic downturn weighed on demand.
ArcelorMittal repeated its guidance for its 2016 core profit to be above $4.5 billion, compared to the $5.2 billion achieved in 2015.
"Despite the steel spread recovery losing momentum in recent weeks, the impact of lagged prices will be an important support for operating results as we move in to a period of seasonally slower steel demand," the company said in a statement, referring to the "spread" between the price for steel and cost of raw materials.
Some analysts had expected the group to increase its outlook.
The group kept its outlook for global apparent steel consumption to grow by up to 0.5 percent, though it downwardly adjusted its outlook for steel market in the United States, because of a tightening of supply resulting in lower inventories. (Reporting by Robert-Jan Bartunek; editing by Philip Blenkinsop)