US President Donald Trump said on Monday a deal with Iran on its nuclear program was possible, crediting economic sanctions for curbing activities Washington has said are behind a spate of attacks in the Middle East."I really believe that Iran would like to make a deal, and I think that's very smart of them, and I think that's a possibility to happen," Trump said during a news conference with Japan's Prime Minister Shinzo Abe in Tokyo."It has a chance to be a great country with the same leadership," Trump said. "We aren't looking for regime change -- I just want to make that clear. We are looking for no nuclear weapons."Tensions have risen between Iran and the United States after this month's attack on oil tankers in the Gulf region.Washington, a firm backer of Tehran's regional rival Saudi Arabia, has blamed the attacks on Iran, which denies the accusations.The United States has deployed a carrier strike group and bombers to the Mideast region and an extra 1,500 troops to the Gulf, prompting fears of a conflict.Trump's comments came after his national security adviser John Bolton said on Saturday that the United States had "deep and serious" intelligence on threats posed by Iran, without providing details. Trump, on a four-day visit to Japan, welcomed Abe's help in dealing with Iran after broadcaster NHK said Japan's leader is considering a trip to Tehran as early as mid-June. Iran said a visit was unlikely in the near future."I know for a fact that the prime minister is very close with the leadership of Iran, and we'll see what happens," Trump said.During his joint news conference with Trump, Abe said Japan would do what it can on the Iran issue."Peace and stability of the Middle East is very important for Japan and the United States and the international community as a whole," Abe said.Trump last year withdrew the United States from a 2015 international nuclear deal with Iran, and is ratcheting up sanctions in an effort to end Iran's international sales of crude oil and strangle its economy.Japan was a major buyer of Iranian oil for decades before the U.S. sanctions -- which Trump said were taking effect."They were fighting in many locations," he said of Iran. "Now they are pulling back because they have serious economic problems." Bolton, who has spearheaded an increasingly hawkish U.S. policy on Iran, described recent bomb attacks on tankers off the United Arab Emirates and a pipeline pumping station in Saudi Arabia, as well as a rocket attack in Baghdad's Green Zone as "manifestations of concern" about Iran.Iran has distanced itself from the bombings and on Sunday, its foreign minister, Mohammad Javad Zarif, said his country will defend itself against any military or economic aggression.