Washington would support "the will of the Iranian people and stand behind them: John Bolton
Iran's Islamic revolution four decades ago inflicted "failure and broken promises" on the country, President Donald Trump's chief foreign policy advisor said on Monday.
"It's been 40 yrs of failure. Now it's up to the Iranian regime to change its behavior, and ultimately up to the Iranian people to determine the direction of their country," national security advisor John Bolton tweeted on the anniversary of the upheaval.
Mr Bolton said Washington would support "the will of the Iranian people, & stand behind them to ensure their voices are heard."
Mr Bolton, a leading hawk in the Trump administration's attempt to weaken Iranian influence, was tweeting as a huge crowd in Tehran gathered to celebrate the 1979 revolution, in which Muslim leader Ayatollah Ruholla Khomeini ended the centuries-old rule of the royal dynasty.
Iranian President Hassan Rouhani told Iranians they should resist a "conspiracy" involving Washington.
The Trump administration has pushed hard to weaken Iran and what it says is Tehran's "destabilizing" influence.
The two countries have not had diplomatic relations since 1980, and Trump has pulled the United States from an international agreement meant to reward Iran for giving up nuclear weapon ambitions.