[WASHINGTON] The US economy grew faster than originally reported in the July-September period and prices remain tame, but amid the unresolved trade war with China economists and businesses note some worrying issues persist.

Higher exports and residential investment helped boost growth to a 2.1 per cent annual rate from the 1.9 per cent estimated last month for the third quarter, according to the more complete data the Commerce Department released Wednesday.

But economists note the apparent good news on the economy is tempered by some concerning elements, reflected once again in a nationwide survey by the Federal Reserve, showing continued concerns about the impact of tariffs and trade tensions.

Business investment, which has been hit hard by President Donald Trump's trade war with China, has declined sharply but since it dropped by less than originally reported, falling 2.7 per cent rather than three percent in the first estimate, that smaller decline helped growth.

Meanwhile, businesses building up their inventories of products added nearly 0.2 points to the GDP calculation, according to the revised data. While that could be due to companies stockpiling ahead of announced tariffs, it could also reflect slowing consumption.

"In short, slightly stronger than before, but mainly because of inventories. That data continue to show growth slowing, but not dramatically," said economist Jim O'Sullivan of High Frequency Economics.

The consensus among economists predicted no revision to the GDP result.

But some correctly forecast the upward revision which puts the third quarter on track to best the two per cent growth in the second quarter, after the 3.1 per cent expansion in the first three months of the year.

Consumption, the traditional driver of growth, accounting for 70 per cent of US GDP, increased 2.9 per cent, with a strong gain in spending on durable goods such as cars or appliances, according to the data. However, that is a much smaller increase than the prior quarter.

Investment in real estate market jumped 5.1 per cent, the strongest in two years, boosted by low interest rates.

Exports, which fell 5.7 per cent at the height of the trade war in the second quarter, recovered slightly in the latest quarter, rising 0.9 per cent - two-tenths stronger than originally reported.

Imports also were stronger than previously estimated, rising by 0.8 per cent.

The latest reading on GDP growth "indicates the economy is not about to fall off a cliff," said Gregory Daco of Oxford Economics.

MORE SLOWING AHEAD?

"However, the lingering global industrial slump, persistent trade policy uncertainty and cooling income growth all point to weaker activity in the coming months," he said in an analysis.

The Fed has lowered overnight interest rates three times this year as insurance against the global and domestic economic slowdown.

But the Fed's "beige book" survey of businesses, farmers and bankers showed the continued negative impact of trade tensions and tariffs, with most of the 12 regions showing only slight growth.

Three stagnated, while manufacturing in the majority of regions showed no growth.

In Richmond, businesses continue to "face constraints from tariffs and trade uncertainties," which has led to higher costs, the survey showed.

In Atlanta, trade policy is "a potential downside risk to their outlook," while energy companies in Dallas complained the tariffs and uncertainty were "squeezing margins" and "making planning difficult."

Mr O'Sullivan noted that the manufacturing sector "is disproportionately exposed to weakening in foreign demand."

Amid the deluge of data ahead of Thursday's Thanksgiving holiday, another report showed the Fed's preferred inflation measure - the PCE price index - held steady at a low 1.3 per cent in October remaining well below the Fed's two per cent inflation goal.

Excluding volatile food and energy prices, the "core" PCE inflation index slowed slightly to 1.6 per cent from 1.7 per cent in the prior month.

Looking ahead to the fourth quarter, the Commerce Department in a separate report said durable goods orders in October also were far better than expected, rising 0.6 per cent rather than the sharp decline economists had forecast.

Without the volatile transportation sector, orders also rose by 0.6 per cent.

But economists say they are suspicious of the data, which they expect to be revised.

AFP