"Today, the big thing is coming", he writes on the social network Truth Social on Thursday.
At the same time, he calls the first weeks, after he took over the presidency in January, perhaps the best weeks ever. And he concludes the post with his election slogan about making the USA great again (in capital letters and with three exclamation marks).
Trump's post comes ahead of a planned meeting with Indian Prime Minister Narendra Modi at the White House.
Trump has previously hinted that tariffs are on the way, but does not go into any details in the post.
Simply, if they tax us, we will tax them, he said to journalists on Sunday, according to NBC News.
Trump began his second presidential term in January with a 10 percent tariff on all goods from China and 25 percent tariffs for neighboring countries Mexico and Canada. The tariffs against China have come into effect, but Mexico and Canada have, after negotiations on stricter border controls, been given a 30-day reprieve.
On Monday, Trump followed up this first round of tariffs by signing a decree on 25 percent tariffs on steel and aluminum, regardless of where they are imported from. Something that could affect Swedish steel companies.
