WASHINGTON • The US trade deficit fell for the first time in six years last year as the White House's trade war with China curbed the import bill, keeping the economy on a moderate growth path despite a slowdown in consumer spending and weak business investment.

The report from the Commerce Department on Wednesday also showed the Trump administration's "America First" agenda decreased the flow of goods last year, with exports posting their first decline since 2016.

With tensions in the 19-month US-China trade war easing, last year's narrowing in the deficit is unlikely to be repeated.

"Since that entire drop came from the huge change in the China deficit, don't expect further declines in the years to come," said chief economist Joel Naroff at Naroff Economic Advisors in Pennsylvania.

The trade deficit dropped 1.7 per cent to US$616.8 billion (S$854.2 billion) last year, declining for the first time since 2013. That represented 2.9 per cent of gross domestic product, down from 3 per cent in 2018.

Goods imports plunged 1.7 per cent last year, also the first decrease in three years. The United States imported 2.4 billion barrels of crude oil, the fewest since 1992, as the country significantly reduced its dependence on foreign oil amid a surge in production and exploration.

It also imported fewer capital and other goods. The 1.3 per cent tumble in exports was led by decreases in shipments of capital goods, industrial supplies and materials, and other goods.

At the height of the US-China trade war last year, Washington slapped tariffs on billions worth of Chinese goods, including consumer products, thumping imports.

The politically sensitive goods trade deficit with China plunged 17.6 per cent to US$345.6 billion last year.

REUTERS