The trade deficit is the difference between how much goods and services the US imports from other countries and how much it exports.
Reducing the gap is a key plank of Mr Trump's policies.
But in 2018, the US exported fewer goods compared with how much it bought.
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Mr Trump claims that the US is being "ripped off" by other nations and wants countries to lower their tariffs on US goods and buy more of them.
However, official data shows that while exports of US goods and services rose by USD148.9bn last year, imports jumped by USD217.7bn.
It means that the gap is the widest since 2008, when the global financial crisis hit and the US fell into recession.
The deficit in goods and services during December also hit a near 10-year high of USD59.8bn.
Exports to the rest of the world fell 1.9% to USD205.1bn, while imports rose by 2.1% to USD264.9bn.
The US is currently locked in a trade battle with China over what it claims are unfair trade practices, resulting in tit-for-tat tariff increases on each others' goods.
New data shows that the trade gap between the US and China widened last year by USD43.6bn to USD419.2bn as exports of American products and services fell, but imports from China rose.