Former U.S. Vice President Kamala Harris has accused President Donald Trump of recklessness for threatening war crimes in Iran after he launched a “disastrous” conflict with no strategy to end it.

Ms Harris’ remarks followed Mr Trump’s threat that “a whole civilisation will die tonight” if Iran failed to open the Strait of Hormuz before the expiration of his self-imposed 8:00 p.m. Eastern Time Tuesday deadline.

“The president of the United States is threatening to commit war crimes and wipe out a ‘whole civilisation’—all because he started a disastrous war of his own making and had no plan and no strategy for how to end it,” said Ms Harris.

The former vice president described Mr Trump’s actions as reckless and despicable, stating that Americans opposed them.

Ms Harris criticised the president for endangering the lives of military officers and “destroying” America’s global reputation.

“This is abhorrent, and the American people do not support this.

“Trump’s recklessness is needlessly putting our brave service members in harm’s way, destroying America’s global standing, and making life even more unaffordable for the American people,” she stated.

Ms Harris urged Americans to “oppose funding this illegal war of choice.”

The politician had, on March 1, condemned Mr Trump’s airstrikes on Iran, saying they undermined global confidence in the U.S. leadership.

Ms Harris acknowledged concerns over Iran’s nuclear ambitions but said military escalation was not the appropriate strategy to address the threats.