Activity at U.S. factories continued to pick up in August, another sign of a recovery in global manufacturing.

A closely watched manufacturing index from the Institute of Supply Management edged up to 55.7 from 55.4 in July. Economists had been forecasting a modest decline.

Instead the reading was the third straight month of growth after the purchasing managers' index fell to 49 in May. Any reading above 50 indicates growth in the sector.

The report follows comparable reports Monday that showed a rebound in Chinese manufacturing, and the fourth straight month of growth at factories across the euro zone. Manufacturing in Italy and Spain enjoyed the best growth in more than two years.

Tuesday's U.S. manufacturing reading showed the new orders index jumping by nearly 5 percentage points to a reading of 63.2

The report also follows last week's government reading that showed stronger economic growth in the second quarter than previously estimated. And it comes ahead of the key August jobs report due out this Friday. Economists surveyed by Briefing.com forecast that employers added 177,000 jobs in the month, up from the 162,000 gain reported for July.