President Donald Trump ordered new sanctions on Iran Wednesday, just days after the U.S. dispatched an aircraft carrier and B-52 bombers to the Persian Gulf over what it described as a new threat from Tehran .

The sanctions target Iran’s steel, aluminum, copper and iron sectors, which provide foreign currency earnings for the nation’s sagging economy. The White House said it would continue its “maximum pressure” campaign on the Iranian government until it stops supporting terror groups, ends destabilizing activities in the region, gives up any nuclear weapons efforts and ends any development of ballistic missiles.

“We call on the regime to abandon its nuclear ambitions, change its destructive behavior, respect the rights of its people, and return in good faith to the negotiating table,” Trump said.

The United States, Germany, Britain, France, Russia, China and the European Union signed a deal with Iran in 2015 that lifted international sanctions in exchange for Tehran limiting its nuclear program, including restricting uranium enrichment for 10 years.

One year ago, Trump pulled out of the agreement, which he called “the worst deal in history.” He said the accord should also have restrained Iran’s ballistic missile program and curbed what his administration considers Tehran’s malign activities in the region. The administration then re-imposed crippling economic sanctions on Iran that had been lifted under the agreement.

The other nations have remained in the deal and have tried to provide Iran with enough economic incentives to keep the agreement alive.

Iran threatened on Wednesday to enrich its uranium stockpile closer to weapons-grade levels in 60 days if world powers fail to negotiate new terms for its 2015 nuclear deal. Iran has stopped its sale of excess uranium and heavy water as a first step — something required under the deal.

In 60 days, if no new deal is in place, Iran said it would increase its enrichment of uranium beyond 3.67%, which is permitted by the accord. Rouhani did not say how far Iran would be willing to enrich, although the head of its nuclear program again reiterated Iran could reach 20% enrichment within four days. Once a country enriches uranium to around 20%, scientists say the time needed to reach the 90% threshold for weapons-grade uranium is halved.

(AP)