As the war against Iran approaches its sixth week, President Trump told Americans on Wednesday that the U.S. is "on the cusp of ending Iran's sinister threat to America and the world."

In his first formal address to the nation since the U.S. and Israel launched the war on Iran on Feb. 28, Trump did not say, however, when the war would end or how it would end, but said the U.S. was "on track to complete all of America's military objectives shortly."

He warned of an intensified period of strikes on Iran, going beyond his initial timeframe of five weeks.

"We are going to hit them extremely hard over the next two to three weeks. We're going to bring them back to the Stone Ages, where they belong," Trump said.

Iran continued to target countries in the Gulf region with ballistic missiles and drones into Thursday as the U.S. Embassy in Baghdad issued a security alert, warning of attacks by Iran-backed militias.

Trump said the discussions with Iran were ongoing as he described Iran's new leaders as "less radical and much more reasonable." But he warned that if Iran failed to reach an agreement, the U.S. military would target the country's energy plants and its oil.

"We have all the cards," he added. "They have none."

In an initial reaction to Trump's speech, Esmail Baghai, a spokesman for Iran's foreign ministry said Iran "will not tolerate this vicious cycle of war, negotiations and ceasefire and then repeating the same pattern."

"This is disastrous not only for Iran, but for the entire region and beyond," Baghai said. "We are defending against an illegal war."

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