Trump warns Iran ahead of talks, says its leaders should be 'very worried'

President Donald Trump sent a fresh warning to Iran's leaders as US military forces amass in the region, the latest sign that diplomatic negotiations between Washington and Tehran could be breaking down.

"I would say he should be very worried, yeah. He should be," Trump said in an interview with NBC News yesterday (4 February), when asked about Iran's supreme leader. "As you know, they are negotiating with us."

Trump's remarks come after Secretary of State Marco Rubio said Washington is open to upcoming talks with Iran and that a location is "being worked through," but stressed the discussions can't be restricted to nuclear issues.

Amid confusion over where the talks will take place and what topics will be covered, Rubio said Wednesday the US side thought an agreement had been reached for the meeting to be held on Friday in Turkey.

"As far as the talks are concerned, you know, I think the Iranians had agreed to a certain format — for whatever reason, it's changed in their system," Rubio told reporters. "We'll see if we can get back to the right place. But the United States is prepared to meet with them."

Iran has asked for the discussions — which follow repeated threats by Trump to strike the country if it doesn't agree to a deal — to be moved to Oman from Turkey and to exclude the participation of regional countries, people familiar with the matter said earlier. The White House hasn't commented on any request of that nature.

Iran also wants to limit the discussions to its nuclear programme, but Rubio said that "for talks to actually lead to something meaningful, they have to include certain things." That includes Tehran's ballistic-missile programme, sponsorship of regional militant groups and the treatment of its people, Rubio said, adding White House Middle East Envoy Steve Witkoff is prepared and ready to attend a summit.