The Luxembourg-based company hosts an investor day starting at 1230 GMT in a far less buoyant environment than when it said at the end of July that it saw no repeat of last year's sharp second-half slowdown.

The group has since revealed plans to idle three blast furnaces in Europe -- in Belgium, France and Germany -- because of low demand. Further end-user weakness, lower steel prices and de-stocking could force further capacity cuts in the weeks ahead.

It cut production by around a half in the depths of the 2008/2009 downturn and, while few expect such a radical measure for now, analysts say the company is likely to focus on its cost-savings plan, which has not been a central feature of presentations so far this year.

In July, ArcelorMittal said a continued recovery of underlying demand meant steel shipments in the second half should be higher than a year earlier. That may now be too optimistic.

Global growth expectations have been cut sharply in the past two months. The International Monetary Fund cuts its forecast for global economic expansion to 4.0 percent this year and next from respectively 4.3 and 4.5 percent and warned Europe and the United States could slip into recession in 2012.

Current market consensus expectations are for ArcelorMittal to produce a core profit (EBITDA) at the upper end of the company's own $2.4-2.8 billion guidance range in the third quarter and for the same figure in the fourth, Thomson Reuters I/B/E/S data show.

However, customer de-stocking and a possible margin squeeze could yield a weaker final three months.

Hot-rolled steel cord prices in Europe continued their steady rise in August, but have come off 3 percent in the past two weeks, according to Steel Business Briefing. However, iron ore prices are up 2 percent in the same period, Metal Bulletin data shows. ArcelorMittal shares have plunged 50 percent in the past two months, while the STOXX 600 index is down 20 percent and the index's basic resource components 30 percent lower.