US President Donald Trump said the American military campaign against Iran is “nearing completion,” while warning that Washington is prepared to intensify strikes over the next two to three weeks if necessary.

Oil prices climbed more than $5 on Thursday, following Trump's speech which gave no specific timeline to ‌end the war, fanning investor fears about sustained disruptions to supply. Brent crude futures rose $6.33, or 6.3%, to $107.49 per barrel by 0407 GMT. US West Texas Intermediate crude ​futures were up $5.28, or 5.3%, to $105.40 per barrel, Reuters said.

In remarks outlining the progress of what he called Operation Epic Fury, Trump said the United States was close to achieving its military objectives but would continue operations until they were fully secured.

“I have made clear from the beginning of Operation Epic Fury that we will continue until our objectives are fully achieved. Thanks to the progress we’ve made, I can say tonight that we are on track to complete all of America’s military objectives shortly — very shortly. We are going to hit them extremely hard over the next two to three weeks,” Trump said.

He added that the US would bring Iran “back to the stone ages where they belong,” while noting that diplomatic discussions were continuing. “We have all the cards; they have none,” he said.

According to a CNN report, Trump’s comments signaled that Washington remains prepared to escalate military pressure even as diplomatic contacts continue.

The president claimed the US military had inflicted severe damage on Iranian forces during the past month of operations.

“As we speak this evening, it has been just one month since the United States military began Operation Epic Fury targeting the world’s number one state sponsor of terror, Iran,” Trump said. “In these past four weeks, our Armed Forces have delivered swift, decisive, overwhelming victories on the battlefield.”

He said Iran’s naval and air capabilities had been heavily degraded, while missile and drone launch capacity had been sharply reduced.

“Tonight, Iran’s navy is gone. Their air force is in ruins. Their leaders, most of them — the terrorist regime they led — are now dead. Their command and control of the Islamic Revolutionary Guard Corps is being decimated as we speak,” Trump said.

Trump reiterated that preventing Iran from obtaining nuclear weapons remained the central objective of the campaign.

“From the very first day I announced my campaign for President in 2015, I have vowed that I would never allow Iran to have a nuclear weapon,” he said, adding that a nuclear-armed Iran would pose what he described as an intolerable threat to global security.

He said the US military objective was to systematically dismantle Iran’s ability to threaten American interests or project power beyond its borders.

“As I stated in my announcement of Operation Epic Fury, our objectives are very simple and clear. We are systematically dismantling the regime’s ability to threaten America or project power outside their borders,” Trump said.

The president also acknowledged domestic concern over rising fuel prices, blaming recent increases on attacks targeting commercial shipping and regional energy infrastructure.

“Many Americans have been concerned to see the recent rise in gasoline prices here at home. This short-term increase has been entirely the result of the Iranian regime launching deranged terror attacks against commercial oil tankers and neighbouring countries that have nothing to do with the conflict,” he said.

Trump urged countries affected by supply disruptions to buy American oil and take a stronger role in securing regional shipping lanes, including the Strait of Hormuz.

“To those countries that can’t get fuel... buy oil from the United States of America; we have plenty,” he said. “Go to the Strait and just take it. Protect it. Use it for yourselves. Iran has been essentially decimated. The hard part is done.”