SINGAPORE, Aug 18 (AFP) - Singapore's key non-oil domestic exports (NODX) grew nearly 11 percent in July from a year ago, lifted largely by strong demand for pharmaceuticals and petrochemicals, the government said Monday.

NODX rose an annual 10.8 percent last month to 9.6 billion Singapore dollars (5.5 billion U.S.) but on a month-on-month basis, it fell three percent, International Enterprise Singapore (IE Singapore) said in a statement.

The year-on-year figure was higher than economists' forecasts of 7.5-10 percent in a poll by financial news wire AFX-Asia, and was the second fastest growth in four months after the 18.7 percent expansion in June.

Total trade in July grew 2.9 percent on the year to 39.5 billion dollars. IE Singapore, the government trade body, said the July expansion was supported by shipments of non-electronics products which "remained healthy."

"The robust performance was driven by larger shipments of pharmaceuticals to (the European Union), petrochemicals to regional markets like Hong Kong, Taiwan, and Malaysia, as well as primary chemicals to China," it said.

Exports of electronics, which account for a major portion of NODX, continued to expand with a 2.4 percent rise in July. "This continued growth was sustained mainly by larger shipments of disk drives and ICs (integrated circuits) and parts during the month," IE Singapore said.

But this was partially pulled down by weak demand for other key components including personal computers, printers and telecommunication equipment, the trade body said.

Shipments to the U.S., the city-state's biggest NODX market, fell almost 10 percent in July after rising 15.2 percent in the preceding month and the weak performance was due to a 13.7 slump in electronic demand from the world's largest economy, IE Singapore said.

But the poor NODX figure to the U.S. was negated by a 24 percent jump in similar shipments to the EU and 23 percent expansion in exports to China and Hong Kong combined.

The closely watched monthly NODX figure is a key barometer of the health of Singapore's trade-dependent economy.

Slightly more than half of NODX is made up electronics which itself contributes to almost half of the city-state's industrial output.