PARIS: US Secretary of State Marco Rubio on Tuesday said he saw no need to resume major combat operations against Iran because economic sanctions and other restrictions were working so effectively.
"The economic campaign (against Iran) is so devastating that right now there is no need for major combat operations," Rubio said after a meeting of G7 foreign ministers in Paris. "That's what I told our allies here today."
President Donald Trump "has concluded that for the time being there is no need for major combat operations because we are achieving the same objective by economic means," Rubio said.
But if Iran were to cross "red lines" then the "US military stands ready", said Rubio, warning of a "terrible price" for Tehran.
European members of the G7 had pressed Rubio at the meeting of foreign ministers of the group in Paris to avoid any new escalation against Iran.
In a surprise move, Qatar's Prime Minister Sheikh Mohammed bin Abdulrahman Al Thani joined talks on the G7 sidelines with four European top diplomats and the Saudi foreign minister hours after meeting Trump to discuss ending Washington's war with Iran, Paris said.
Trump had said after meeting Al Thani -- a key mediator who is also Qatar's foreign minister -- that there was momentum toward ending the war, which erupted on February 28 with the killing of supreme leader Ali Khamenei.
"The economic pain that is being inflicted on Iran right now and on that regime is extraordinary and it is growing every day," said Rubio, saying Iranian oil supplies were drying up due to US blockades.
"This radical regime of lunatics is imposing this on their own people," he said, referring to the Islamic republic's clerical leadership.
But Rubio also appeared downbeat about the prospects of a deal with Tehran, saying Iran currently did not appear realistic about negotiations.
"Iran would love a deal. The problem is, the conditions they continue to place are absurd. They're not even serious. But that could change," he said.
But he added: "Eventually, you have to eat, you have pay your own fighters, your own security forces. I think as time goes on that will have an impact... Eventually economic realities penetrate the skull of the most radical lunatic".
French Foreign Minister Jean-Noel Barrot, who chaired the meeting in Paris, warned that the risk of a new escalation between the United States and Iran "has not been completely ruled out".
"Otherwise, we would not have devoted so much time and energy over the past two days to addressing these issues" with Rubio and the Qatari premier, Barrot said.
British foreign minister Ed Miliband urged an "all-out diplomatic effort" to end the conflict, warning a stalemate of "no war, no peace" was causing economic damage.
"The status quo is bad economically for us and it's not a stable equilibrium," said Miliband, urging a full reopening of the Strait of Hormuz energy transit hub.