Donald Trump warns Iran against restarting nuclear program

U.S. President Donald Trump warned Iran on Tuesday not to follow through with threats to restart its nuclear program, as he and French President Emmanuel Macron struggled to find common ground on saving the 2015 Iran nuclear deal.

Meeting Macron in the Oval Office after a colorful welcome ceremony in honor of the French leader, Trump heaped scorn on the nuclear accord negotiated by his predecessor, former president Barack Obama, and aimed at stopping Iran from getting a nuclear weapon.

Iran has said it will ramp up its nuclear program if the deal collapses and a senior Iranian official said on Tuesday that Tehran might quit a treaty designed to stop the spread of nuclear weapons if Trump scraps the agreement.

"If they restart their nuclear program, they will have bigger problems than they have ever had before," Trump said.

Trump called the agreement a "terrible deal" that was "insane" and "ridiculous" because it did not deal with ballistic missiles or Iran's activities in conflicts in places like Yemen or Syria.

"We made this terrible deal but we're going to discuss it," he said. Under the deal, Iran agreed to curb its nuclear ambitions in return for relief from economic sanctions. Tehran says its nuclear program is only for peaceful means.

Macron came to Washington hoping to persuade Trump to keep the United States in the Iran agreement, saying it offered the best chance to constrain Tehran, imperfect as it may be.

He told Trump the accord is part of a "broader picture" of security in region.

"On Iran, we must contextualize this subject within the challenges of the region. There is the situation in Syria, there is security in the entire region and I think, in any case, we share a common goal of avoiding an escalation and proliferation of nuclear weapons in the region. So the question is what is the best path," Macron said.

European calls for exemptions from Trump's plan for 25 percent tariffs on steel imports are also on their agenda, as well as the U.S. president's desire to withdraw U.S. forces from Syria as soon as practicable.

Macron, whose visit will be followed by one on Friday from German Chancellor Angela Merkel, has called on Trump to keep troops in Syria for the time being to ensure the defeat of Islamic State militants.

A 21-gun salute echoed across the South Lawn and a flute-playing fife and drum corps, in red-coated uniforms and tri-corner hats, marched by Trump and Macron and their wives, Melania Trump and Brigitte Macron in a welcoming ceremony on Tuesday.

In the evening, the Trumps are to host the Macrons at the first state dinner conducted by Trump since he took power.

Trump, in welcoming remarks, thanked France for joining with the United States and Britain in launching airstrikes in Syria earlier this month in response to a chemical weapons attack blamed on Syrian President Bashar al-Assad.

He said he and Macron had developed over the past year "a wonderful friendship" that is "a testament to the enduring friendship that binds our two nations."

Macron, in his remarks, called for the two countries to work together against Islamist militants, on North Korea and Iran, on "free and fair trade," and on climate change.

"It is together that we will counter the proliferation in weapons of mass destruction, whether it is in North Korea or in Iran," Macron said.

He alluded to Trump's withdrawal last year from the Paris climate accord, saying "we do not always agree on the solution," but stressed "the fate of our children is at stake."