Outside what was once the U.S embassy in Tehran, Iranians shouted "Death to America and set fire to the Stars and Stripes on Sunday (November 4).

Such chants may not be rare here - especially on this day, the anniversary of the 1979 seizure of the U.S. embassy.

But this year there's added vitriol.

And that's because on Monday (November 5) the U.S. will reimpose sanctions targeting Iran's key oil sector.

At the Tehran rallies on Sunday (November 4), the head of Iran's powerful Revolutionary Guards described that as "economic and psychological warfare".

"America's plots and plans", he said, "will be defeated through continued resistance by the people." Trump's decision in May to withdraw from the 2015 Iran nuclear deal and reimpose sanctions is designed to force Tehran to halt its nuclear and ballistic missile programs outright, as well as its support for proxy forces in conflicts across the Middle East.

On Friday (November 2) the White House said it would temporarily allow eight jurisdictions to keep importing Iranian oil.

The continuing animosity between the Washington and Tehran has a lot to do with what happened here 29 years ago.

Hardline students stormed the U.S. embassy on November 4, 1979 soon after the fall of the U.S. backed Shah.

52 Americans were held hostage for 444 days, and the two countries have been enemies ever since.