French President Emmanuel Macron presented Lebanon's political establishment with two choices during a trip that ended Tuesday: implement reforms, and vital international aid will flow plentifully, but continue on the same path, and the doors to assistance will slam shut - and the country's ossified political leadership may be directly targeted with sanctions.

"I did not come today to give a warning, but I returned to help Lebanon and accompany it to its future," Macron said on Tuesday, 100 years since colonial France declared the founding of Greater Lebanon.

Macron arrived in Beirut on Monday with the aim of pushing the country's sectarian leaders to find consensus over reforms and over the need to end decades of corruption and mismanagement that have devastated the country. He pledged to hold an aid conference for the economically-devastated nation at the end of October if reforms are commenced.

His previous visit came just days after a monstrous explosion last month killed 190 people, injured more than 6,000 and wrecked half of the city, causing up to $4.6bn in material damage, according to a World Bank assessment.

At the time, Macon came bearing a message that change was necessasry if the country was to avoid total collapse.

"You are at a critical moment in your history where the political system must be reformed," he said on Tuesday.

"When a country disintegrates, you never know when it will be reborn."

New PM not a 'messiah'

Indeed, there is little to celebrate - and much to fear - as Lebanon marks its 100th birthday. In the past year it has witnessed massive protests, deep economic and financial crisis, a surging coronavirus outbreak and one of the biggest non-nuclear blasts ever recorded.

Since Macron's last visit, Prime Minister Hassan Diab's flailing government resigned and a new Prime Minister, Mustapha Adib, has been appointed by the country's establishment under direct French pressure.

France aimed to ensure that whoever is selected has wide political buy-in, unlike Diab.

Macron admitted that Adib was not a "messiah" and contended that Adib knew that he was backed by "political forces that have lost the confidence of the public".

Nevertheless, he said Adib was able to form a capable government and to implement the needed reforms. And Macron said he had heard encouraging words from political leaders.

He split Tuesday between ceremonial gestures - a visit to the destroyed Beirut port and planting a cedar tree, the country's national emblem - and tete-a-tete meetings with politicians, whom he summoned to the ambassador's residence.

Macron told reporters that they had pledged to form a government within 15 days - unprecedented in Lebanon's recent history, where government formation usually take many months.

The government would then have to implement reforms to the crippled electricity sector and the insolvent financial sector within three months, and hold early parliamentary polls within a year.

Macron promised to return by December to follow up on the reform process.

Sanction threats

If reforms are not implemented, Macron said he would inform the international community that no aid could flow and he would talk openly about those in Lebanon who were blocking change.

"We will not give Lebanon a carte blanche, or a blank check," he said.

He also said he did not rule out sanctions against political leaders, but said that France would first have to prove crimes such as corruption or terrorism had been committed.

A western diplomat told Al Jazeera that Macron was keeping the option of sanctions open as "a stick he can wave" at politicians.

This includes the threat of sanctions against President Michel Aoun's son-in-law, Gebran Bassil, who heads the country's largest party in terms of its share of seats in parliament.

However, the source said that there were no sanctions currently being prepared, as the international community waits for the Lebanese response to Macron's initiative.

All political leaders have so far expressed their openness to the French initiative, including Hezbollah and Aoun. Several leaders have also called for Lebanon to finally make the move to being a secular state - a shift mandated by its constitution - though they have also said this in the past.

Currently, all seats in parliament are allocated by sect, and top state positions are meted out along religious lines.

Macron was repeatedly asked to justify his decision to give Hezbollah a seat at the table by meeting with a top Hezbollah official.

The Iran-backed armed group and political party is blacklisted as a terrorist group by western nations including the United States, the United Kingdom and Germany, but France maintains relations with its so-called "political wing".

Macron said Hezbollah was a major constituent of the Lebanese population, with representation in parliament, and it would be foolish to exclude the group from the reform process.

He said that the next round of reform talks with Lebanon would broach the thorny issue of the group's arsenal, which rivals that of the Lebanese army.

"Will we get to results directly? I don't know," said Macron. "But it shouldn't be a taboo."