New Delhi, June 1 -- US manufacturing's headline strength masks a fragile near-term outlook, with growth expected to slow once current stockpiling runs its course and inflation pressures intensify, S&P Global said in a report on Monday.

"The headline PMI has hit a four-year high, with strong factory production growth for a second successive month," said Chris Williamson, Chief Business Economist at S&P Global Market Intelligence.

"But since the outbreak of war in the Middle East we have seen production and demand buoyed by stock building as companies worry over rising prices and supply difficulties. This stockpiling was again widely evident in May and makes it hard to take an accurate reading on the underlying health of the manufacturin...