Defense Secretary Pete Hegseth said the coming days of the war with Iran will be decisive, adding that the U.S. would “negotiate with bombs” until Tehran relinquishes its ambitions.

“Iran knows that, and there’s almost nothing they can militarily do about it,” he said at a briefing on Tuesday.

“We would much prefer to get a deal. If Iran was willing to relinquish material they have and ambitions they have…great, that’s the goal. We don’t want to do more militarily than we have to,” Hegseth said.

“Our job is to ensure that we compel Iran to realize that this new regime, this regime in charge, is in a better place if they make that deal,” he added.

Asked about the progress of talks with Tehran in general, he deferred to U.S. negotiators. “We stand right there next to our negotiating team—always willing and prepared to put them in an even better position,” he said.

Hegseth said the Pentagon’s goal is to destroy Iran’s missiles, drones and navy. He didn’t mention opening the Strait of Hormuz as a military objective, saying that was a mission with which other nations should help.

At Tuesday’s briefing, neither Hegseth nor Gen. Dan Caine, chairman of the Joint Chiefs of Staff, mentioned the latest number of U.S. casualties. According to recent U.S. military statements, 13 U.S. troops have been killed in the war and more than 300 wounded.

The comments came shortly after President Trump lashed out on social media at U.S. allies, pushing them to launch their own operation to wrest control of the strait from Iran, blaming countries like the U.K. for not joining the U.S.-Israeli mission against the Islamic Republic.

The administration has increasingly insisted that other countries have more at stake from the closure of the strait than the U.S., because they depend more heavily upon it for their energy supplies.

Meanwhile, U.S. officials said the Nimitz-class aircraft carrier USS George H.W. Bush and its accompanying warships are deploying to the Middle East, joining the USS Abraham Lincoln and the USS Gerald R. Ford carrier strike groups in the region.

The U.K. will deploy a small number of additional troops and air-defense systems to the Middle East, including a Sky Sabre system to Saudi Arabia, the Ministry of Defense said.

During a trip to allied Gulf nations, U.K. Defense Secretary John Healey said other air-defense and counterdrone systems had also arrived in Bahrain and Kuwait.

The U.K. has said it would help allies in the region to defend themselves from Iranian attacks.

The Iranian parliament earlier approved a plan to collect tolls on vessels traveling through the strait, state media reported. The proposal would require agreement from other countries next to the strait. The state media didn’t specify how much the tolls would be.

Beijing and Islamabad on Tuesday issued a joint five-point peace initiative to “restore peace and stability” in the region, Pakistan’s and China’s foreign ministries said on social media.

The plan, which calls for an immediate stop to the hostilities, was published online after a meeting between Chinese Foreign Minister Wang Yi and Pakistan’s top diplomat, Ishaq Dar, in Beijing.

The proposal also urges restoring “normal passage” through the Strait of Hormuz and safeguarding civilian sites and critical infrastructure, including energy, desalination and power facilities, as well as peaceful nuclear infrastructure.

Separately, the U.S. hit a large ammunition depot in the Iranian city of Isfahan with 2,000-pound bunker-buster bombs, an official said, while the United Arab Emirates suffered one of the most intense days of Iranian attacks since the first week of the war.

U.S. forces have struck more than 11,000 targets during the monthlong war on Iran, largely focusing on sites that degrade Iran’s offensive capabilities.

Iran launched missiles and drones at Persian Gulf countries and Israel on Tuesday, while Israel continued strikes on Tehran and Beirut.

Iran’s Islamic Revolutionary Guard Corps issued a warning to several major international corporations, alleging their involvement in operations conducted by the U.S. and Israel against Iran, and said they would be treated as “legitimate targets.”

The conflict in Iran and the broader military conflict across the Middle East is projected to cost the region up to $194 billion in lost economic output, according to the United Nations Development Program.

The war will pull as many as four million people into poverty, the United Nations Development Program estimates. Up to 3.64 million jobs could be eliminated as well.

Write to Michael R. Gordon at michael.gordon@wsj.com, Gary Mitchell at gary.mitchell@wsj.com and Alexander Ward at alex.ward@wsj.com