Before then, the candidates, representing the parties La Republique En Marche! and National Rally respectively, will meet on Wednesday evening for what promises to be a fiery head-to-head televised debate, a two-hour event beginning at 7pm GMT.
The first round of voting on 10 April saw Mr Macron secure 27.8 per cent of the vote and Ms Le Pen 23.1 per cent as another ten candidates were knocked out of contention, including socialist Jean-Luc Melenchon and another far-right contender, Eric Zemmour, whose even more extreme positions on immigration enabled Ms Le Pen to position herself as a more moderate choice than she has previously appeared.
Mr Macron, 44, seeking a second term in the Elysee, is leading in opinion polls with a margin varying between 3 and 13 percentage points.
But Ms Le Pen, 53, has significantly narrowed the gap compared to the last presidential election five years ago, when she lost with 34 per cent of the vote to Mr Macron’s 66 per cent, dropping her calls for a “Frexit” from the EU and renewing her focus on domestic concerns.
An equivalent TV debate is said to have sealed the right-winger’s fate in 2017, a night she has said represented the “biggest failure” of her career on which she appeared hesitant, got lost in her notes and made a series of economic blunders that her opponent, then a fresh-faced novice, pounced upon, revealing himself to be significantly better prepared.
This time, French voters are widely reported to be undecided about which candidate to opt for, as tempted as ever by the prospect of change but wary of Ms Le Pen’s past record and associations with Vladimir Putin in light of the war in Ukraine, which Mr Macron has tried in vain to bring to a peaceful conclusion, arguably at the expense of his own campaigning.
The president will seek to appeal to disaffected leftists before Sunday and present a pro-European case for unity against Russian aggression but is vulnerable to challenge on his policy record with the country mired in inflation, while his challenger is hoping to capitalise on anti-Macron, anti-immigrant sentiment to present herself as a realistic alternative for France.
“I want to convince women and men with diverse political points of view,” he has said.
His opponent counters that contention in a new campaign video in which she accuses the president of doom-mongering about the prospect of her victory, declaring: “Fear is the only argument that the current president has to try and stay in power at all cost.”
Additional reporting by agencies