US President Donald Trump announced on Wednesday that he had struck a trade deal with Vietnam under which the country would face a minimum 20 percent tariff and open its market to US products.

The deal comes a week ahead of Trump's self-imposed July 9 deadline for steeper tariffs on US trade partners to take effect if agreements had not been reached.

Trump initially announced that the trade deal had been reached, without providing details.

"It is my Great Honor to announce that I have just made a Trade Deal with the Socialist Republic of Vietnam after speaking with To Lam, the Highly Respected General Secretary of the Communist Party of Vietnam," Trump wrote on his Truth Social platform.

He said that under the "Great Deal of Cooperation," imports of Vietnamese goods will face a 20 percent US tariff, while goods that pass through Vietnam from other countries, or trans-shipments, will see a steeper 40 percent tariff.

"In return, Vietnam will do something that they have never done before, give the United States of America Total Access to their Markets for Trade," he said.

"In other words, they will 'open their market to the United States,' meaning that we will be able to sell our product into Vietnam at ZERO Tariff," he added.

The president said he believed US-made SUVs, "which do so well in the United States, will be a wonderful addition to the various product lines within Vietnam."

General Secretary of the Communist Party of Vietnam Central Committee To Lam welcomed a new trade agreement with the United States during a phone call with Trump, Vietnam News Agency reported.

He urged Washington to soon recognise Vietnam as a market economy and to lift export restrictions on certain high-tech goods.

The two leaders also discussed major directions and measures to further strengthen the Vietnam-US comprehensive strategic partnership in the coming years.

Trump's announcement comes a week before the US has threatened to reimpose steep tariffs on dozens of economies, including the EU and Japan, many of which are still scrambling to reach deals that would protect them from the measures.

Those higher tariffs are part of a package Trump initially imposed in April, citing a lack of "reciprocity" in trading relationships, before announcing a temporary lowering to 10 percent.

Without a deal, Vietnam's "reciprocal tariff" would have risen from the baseline 10 percent to 46 percent.

Since April, Washington had so far only announced a pact with Britain and a deal to temporarily lower retaliatory duties with China.

Both involve the United States maintaining some of Trump's tariffs on the trading partners. (AFP/Xinhua)