On his first trip to Cuba during his third term in office, Brazilian President Luiz Inacio Lula da Silva called the embargo imposed by the United States on the island "illegal" and denounced the island's inclusion on the list of state sponsors of terrorism.
That’s all legal actions the US can take.
You and I agree that they’re unwise and unjustified. But they’re legal.
The UN says it’s in violation of international law, he literally gave you a link…
The UN is a political organization and says whatever countries vote it to say. It’s also not a legislative organization, it’s basically a big political club of people who like to write strongly worded letters about things. Only the UNSC has teeth, and that hasn’t declared it illegal for obvious reasons.