FRANCE'S far-right presidential candidate Marine Le Pen has refused to don a headscarf for a meeting with Lebanon's top Sunni Muslim cleric and walked away from the scheduled appointment after a brief squabble at the entrance.

The debacle topped Le Pen's three-day visit to Lebanon, where she held her first campaign meeting with a head of state.

It put a spotlight on her strong support for secularism and a proposal in her presidential platform that promotes banishing headscarves and other obvious religious symbols in all public spaces.

"I consider the headscarf a symbol of a woman's submission," she told reporters at the end of her visit. "I will not put on the veil."

She compared her refusal to wear the headscarf to the decision by Michelle Obama to decline wearing one during her state visit to Saudi Arabia.

"I note that when Marine Le Pen refuses to don the headscarf, it is criticised, but when Michelle Obama refused to do it in Saudi Arabia, it was considered admirable," she said.

Journalists shouted back that the two situations were not comparable because one was a state visit while the other was to a religious body.

French law bans headscarves in all classrooms except universities. She has proposed extending the 2004 law banning headscarves and other "ostentatious" religious symbols in classrooms to all public spaces.

While the law covers all religions, it is widely viewed as aimed at Muslims.

Asked if she fears her proposal may ignite the anger of the Muslim community, she said: "When in Rome, do as the Romans do."

The incident occurred ahead of a scheduled meeting with Lebanon's grand mufti, Sheikh Abdel-Latif Derian.

Shortly after Le Pen arrived at his office, one of his aides handed her a white headscarf to put on. Following a discussion with his aides that lasted a few minutes, she refused and returned to her car.

She said she had informed her host the night before that she would not wear the scarf but they did not cancel the meeting, adding: "They tried to impose it upon me."

She said the Grand Sheik of Al-Azhar, the head of the Sunni world's most prestigious learning institute, did not require her to don a headscarf. Photos of Le Pen with Ahmed al-Tayeb in 2015 in Cairo show her with her hair uncovered.

The officials at the mufti's office "kept the meeting and consequently put me before a fait accompli", she said. "I stuck to my position, because when I take a position it corresponds to a conviction. If (you don't like it) never mind."

The office of Lebanon's mufti issued a statement saying Le Pen was told in advance through one of her aides that she would have to put on a headscarf during the meeting.

"This is the protocol" at the mufti's office, the statement said. It said the aides tried to give her the headscarf and Le Pen refused.

"The mufti's office regrets this inappropriate behavior in such meetings," the statement said.

Le Pen has tried to raise her international profile and press her pro-Christian stance with her visit to Lebanon, a former French protectorate.

On Monday, she met President Michel Aoun, a Christian, and prime minister Saad Hariri, a Sunni Muslim.

She said Syrian President Bashar Assad was "the most reassuring solution for France", adding that the best way to protect minority Christians is to "eradicate" Daesh.