US and Iranian diplomats opened indirect talks Saturday in Oman in an effort to resolve Western concerns about Iran's nuclear program.

US Defense Secretary Pete Hegseth on Sunday described the first, tentative contacts in Oman as "productive" and "a good step."

He told CBS's "Face the Nation" that while President Donald Trump hoped to never have to resort to a military option, "We've shown a capability to go far, to go deep and to go big."

"Again, we don't want to do that, but if we have to, we will to prevent the nuclear bomb in Iran's hands."

Trump said Wednesday that military action was "absolutely" possible -- in conjunction with Israel -- if the talks in Oman failed.

"If it requires military, we're going to have military," he told reporters. "Israel will obviously be very much involved in that, be the leader of that."

That followed a blunt warning in late March that "if they don't make a deal, there will be bombing."

Trump pulled the United States out of an earlier multi-nation nuclear agreement with Iran in 2018, during his first term in the White House.

Analysts say Iran may now be just weeks away from producing a deliverable nuclear weapon -- though Tehran denies it is building such arms.