WASHINGTON－French President Emmanuel Macron started his three-day state visit to Washington on Monday, which is expected to test his much-vaunted "friendship" with US counterpart Donald Trump, as the leaders tackle deep differences over Iran and other key dossiers.

In an interview broadcast on the eve of his departure, Macron rehearsed the arguments he will likely put to the US leader on trade fights, the Syrian conflict and the imperiled nuclear deal with Teheran that Trump is threatening to quit.

It will be Trump's first hosting of a state visit since he took power in January 2017. But such thorny issues will be on the back burner－with the warm ties between the 40-year-old French leader and his US host instead on full display.

Less than a year after they shared an intimate meal on the second floor of the Eiffel Tower, Trump and first lady Melania will host Brigitte and Emmanuel Macron for a private dinner at Mount Vernon, the home of the first US president George Washington.

The serious business will kick off on Tuesday with meetings at the White House followed by a state dinner, and on Wednesday the centrist leader will demonstrate his English-language skills－a rarity for a French president－in an address to a joint session of Congress.

Iran is set to top the agenda throughout the visit: Trump has set a May 12 deadline for the Europeans to "fix" the 2015 agreement that curbs Teheran's nuclear program in exchange for sanctions relief, threatening otherwise to walk away.

The text cannot be unilaterally reopened, and Iran says it is ready to relaunch its nuclear program－which the West suspects is designed to produce a bomb－if it fails.

"I don't have any Plan B for nuclear－against Iran," Macron told the Fox News Sunday television talk show before heading to Washington, arguing that curbing Teheran's missile program and containing its regional influence could be accomplished in addition to the 2015 accord.

Macron also cited a shared goal as he argued for a long-term US commitment in Syria－where Paris and Washington have cooperated in fighting the Islamic State group and coordinated strikes on alleged Syrian government's chemical weapons installations.

"I think the US role is very important to play," he said.

Finally on trade－the other burning issue on the table－Macron will reiterate Europe's demand that it be definitively spared from punishing new steel and aluminum tariffs, days before a temporary exemption is due to expire.

"You don't make trade war with your allies," he told Fox News.

Merkel said the World Trade Organization's rules offered the right framework and that bilateral agreements could be a good supplement to that, but she stressed that "consensual negotiated solutions" were important.

AFP/REUTERS