President Trump on Monday vowed to step up strikes on Iran — warning, “The big one is coming.”

The president also told The Post that he won’t shy away from sending American ground troops into the Islamic Republic “if necessary” — though he did not believe they would be needed.

Trump pledged to continue the US campaign against the Islamist regime until it was completely defanged, despite the costs. He previously suggested it could last four weeks.

So far, six US service members have been killed — all in Iranian strikes on Kuwait, and America lost three advanced, $31 million F-15E Strike Eagle fighter jets after they were accidentally shot down by the gulf country’s air defenses.

Iran has also attacked all of the US’s allies in the region in retaliation for its assaults, launching drones and ballistic missiles at every nation in the Persian Gulf, as well as Iraq, Israel and even Cyprus.

More than 48 hours after the US’s “Operation Epic Fury” began with the assassination of Ayatollah Khamenei and dozens of his top goons, America is not finished with its bombardment campaign, Trump told CNN’s Jake Tapper.

Follow live updates on the US and Israel’s war with Iran

“We’re knocking the crap out of them,” Trump told the cable-TV anchor.

“I think it’s going very well. It’s very powerful,” he said of the U assault.

“We haven’t even started hitting them hard. The big wave hasn’t even happened. The big one is coming soon.”

Operation Epic Fury saw the US and Israel conduct joint strikes across Iran — a nation of 90 million people around the size of Alaska — over the weekend.

The US hit more than 1,250 targets, including the Islamic Revolutionary Guard Corps headquarters, ballistic missile sites, navy ships and command centers, according to US Central Command. 

The attacks have also reduced Iran’s fleet in the Gulf of Oman from 11 to zero, CENTCOM said.  

Trump launched the order for the attacks while on his way to a Texas primary rally where he danced to “YMCA” and called for “hamburgers for all” at Whataburger, it was later revealed. 

Trump said the attacks would intensify until his goals are completed — as he warned Iranian civilians to stay inside until the fighting concludes.

“Right now we want everyone staying inside. It’s not safe out there,” he said.

The president outlined four objectives for the war in Iran, including the destruction of Iran’s ballistic missile capabilities and its naval capacity. 

Trump also said the US would ensure Tehran will not obtain a nuclear weapon and that “the Iranian regime cannot continue to arm, fund and direct terrorist armies outside of their borders.” 

Secretary of State Marco Rubio said the US was committed to achieving these goals as he echoed Trump’s warning of escalating attacks. 

“The next phase will be even more punishing on Iran than it is right now,” Rubio told reporters on Capitol Hill.

“We will do this as long as it takes to achieve those objectives, and we will achieve those objectives. The world will be a safer place when we’re done with this operation,” he added, while declining to give a timeline. 

Trump estimated that the operation would last four or five weeks but stressed that it could go on longer after Iran warned that it was prepared to take part in a “long war.” 

Along with the missile strikes, Trump told The Post that he was still open to sending troops to Iran depending on how the situation unfolds, with the president noting that the US was “way ahead of schedule” in its goals after the weekend assault.  

“I don’t have the yips with respect to boots on the ground — like every president says, ‘There will be no boots on the ground.’ I don’t say it,” Trump said after launching strikes Saturday to decapitate Iran’s military and political leadership. “I say, ‘Probably don’t need them,’ [or] ‘if they were necessary.’”

Trump also boasted about the strike that killed Khamenei, noting that his administration killed him in one-go after previous alleged Iranian-linked assassination plots targeting the president. 

“I got him before he got me,” he told ABC News. “They tried twice. … I got him first.”

The American attacks led Iran to launch a region-wide counterattack, which led to the death of six Americans as of Monday evening. 

At least four service members were killed when their operations base in Kuwait was struck by Iran, with another four left seriously injured, according to CENTCOM.  

The remains of another two soldiers were located after another strike in the Middle East facility, CENTCOM added, without providing further details. 

The identities of the fallen are being withheld for 24 hours so their families can be officially notified, the military said. 

Trump told Tapper that the extent of Iran’s retaliation against American allies was “the biggest surprise” of the war so far, but the president said it has only steeled his resolve to fight. 

The president told The Post that he wasn’t concerned about Iran using terrorism to repay America for the weekend’s attack.

“We’ll take it out. Whatever. It’s like everything else, we’ll take it out,” Trump said.