DUBAI/WASHINGTON, June 23 (Reuters) -

U.S. President Donald Trump said on Sunday he was not seeking war with Tehran after a senior Iranian military commander warned any conflict in the Gulf region could spread uncontrollably and threaten the lives of U.S. troops.

Tensions remain high between longtime foes Iran and the United States after Trump said on Friday that he called off a military strike to retaliate for Iran's downing of an unmanned U.S. drone out of concern it would have been a disproportionate response.

"I'm not looking for war," Trump said on NBC's Meet the Press program.

U.S. Secretary of State Mike Pompeo repeated to reporters on Sunday that Washington wanted talks with Tehran.

"We're prepared to negotiate with no preconditions," he said. "They know precisely how to find us. I am confident that at the very moment they're ready to truly engage with us we'll be able to begin these conversations. I'm looking forward to that day."

Pompeo also said that "significant" sanctions on Iran to be announced on Monday would be aimed at further choking off resources that Tehran uses to fund its activities in the region.

"We are going to deny them the resources they need to do that, thereby keeping American interests and American people safe all around the world," Pompeo said before leaving to travel for talks on Iran with U.S. allies Saudi Arabia and the United Arab Emirates, Tehran's regional rivals.

Trump has indicated that he would also be prepared to seek a deal to bolster Iran's flagging economy, an apparent move to defuse tensions.

"I think they want to negotiate. And I think they want to make a deal. And my deal is nuclear. Look, they're not going to have a nuclear weapon," Trump said.

Iran played down the impact of any new U.S. sanctions. They were "just propaganda, as all sanctions ... have been imposed and there are no more sanctions left," state-run news agency IRIB quoted Foreign Ministry spokesman Abbas Mousavi as saying.

Iran denies seeking nuclear weapons and refers to a fatwa or religious decree issued in the early 2000s by Iran's top authority Ayatollah Ali Khamenei that bans the development or use of nuclear weapons.

Last year Trump withdrew the United States from a 2015 accord between Iran and world powers that curbed Tehran's nuclear program in exchange for easing sanctions. Relations in the region have worsened significantly since then.

On a visit to Kuwait, the U.S. Special Representative for Iran, Brian Hook, said that the June 28-29 G20 meeting in Osaka, Japan would provide an opportunity to discuss addressing maritime threats in Gulf waters.

"This is a very urgent priority that nations around the world would come together and enhance maritime security ... This is one of the most critical shipping lines and we cannot allow Iran to threaten the free flow of commerce, to threaten lives, to threaten maritime catastrophes," Hook told reporters.

Iran has said it would respond firmly to any threat and warned on Sunday of the risks of a military confrontation.

"If a conflict breaks out in the region, no country would be able to manage its scope and timing," Major General Gholamali Rashid said, according to the semi-official Fars news agency.

"The American government must act responsibly to protect the lives of American troops by avoiding misconduct in the region."

A hawk in Trump's administration, national security adviser John Bolton, sought to maintain military pressure on Iran.

"Neither Iran nor any other hostile actor should mistake U.S. prudence and discretion for weakness. No one has granted them a hunting license in the Middle East," Bolton said during a visit to Israel.

Meanwhile, Iranian lawmakers chanted "Death to America" during a parliament session on Sunday.