John Bolton, the U.S. national security adviser, says the Trump administration is returning to the foreign policy principle of the Monroe Doctrine.

Pressed on why he has chosen to pressure Venezuela under Nicolas Maduro more aggressively than other brutal regimes around the world, Bolton said the White House would be more involved in the affairs of its own hemisphere

"No, I think it's separate [comparing Venezuela to Saudi Arabia]. In this administration, we're not afraid to use the word Monroe Doctrine. This is a country in our hemisphere. It's been the objective of American presidents going back to [President] Ronald Reagan to have a completely democratic hemisphere," Bolton told CNN's Jake Tapper.

"I mentioned at the end of last year that we're looking at the talk of tyranny. Part of the problem in Venezuela is the heavy Cuban presence. 20,000 to 25,000 Cuban security officials by reports that have been in the public. But this is the sort of thing that we find unacceptable and that's why we're pursuing these policies."

The Monroe Doctrine, laid out by James Monroe, the fifth U.S. president, in 1823, envisaged separate spheres of European and American influence. It stood again European colonization in the Americas and interpreted intervention there as a potentially hostile act.

Presidents John F. Kennedy cited the Monroe Doctrine to block the spread of Communism to Cuba and and Reagan referred to it when supporting the Contra rebels in Nicaragua.