Lebanon's Prime Minister Saad al-Hariri has said his stay in Saudi Arabia was to consult with officials there on the future of Lebanon and its relations with its Arab neighbours, dismissing as "rumours" reports about his alleged detention in the kingdom.

Key points: Saad Hariri is expected in Paris' presidential palace on Saturday

Saad Hariri is expected in Paris' presidential palace on Saturday The Lebanese PM would have "a small Arab tour" before travelling to Beirut

The Lebanese PM would have "a small Arab tour" before travelling to Beirut Saudi Arabia's Foreign Minister says there will be no stability in Lebanon unless Hezbollah disarms

Mr Hariri's tweet came hours before he was expected in France two weeks after his surprise resignation in Saudi Arabia.

"All stories spreading about my sojourn and departure or that deal with the circumstances of my family are merely rumours," he added.

French President Emmanuel Macron's office said Mr Hariri is expected in Paris' presidential palace by midday on Saturday (local time).

After Mr Hariri's visit to France, he would have "a small Arab tour" before travelling to Beirut, said Okab Saqr, a member of parliament for Future Movement.

Mr Macron, speaking in Sweden, said Mr Hariri "intends to return to his country in the coming days, weeks".

Mr Hariri's televised November 4 resignation from Riyadh stunned the Lebanese, many of whom saw it as a sign that the kingdom — the Prime Minister's chief ally — had decided to drag tiny Lebanon into the Sunni kingdom's feud with the region's other powerhouse, the predominantly Shiite Iran.

Lebanese President Michel Aoun believed Prime Minister Saad al-Hariri was detained in Saudi Arabia. ( Reuters: Jamal Saidi )

President Michel Aoun, a political ally of Hezbollah, has called Mr Hariri a Saudi hostage and refused to accept his resignation unless he returns to Lebanon.

Saudi officials denied the reports, adding that Mr Hariri was an ally, but railed against Hezbollah, the Lebanese militant group backed by Iran, accusing the two of meddling in the region's affairs and backing anti-Saudi rebels in Yemen.

The move by Saudi-aligned Mr Hariri raised concern in a region already beset by conflict.

Many feared Lebanon's delicate sectarian-based political system could be easily upended if the county is dragged into a battle for regional supremacy between Saudi Arabia and Iran.

Hezbollah is a 'first-class terrorist organisation': Adel al-Jubeir

Saudi Arabia's foreign minister said there will be no stability in Lebanon unless the militant group Hezbollah disarms.

"This is what we hope," Adel al-Jubeir said at a press conference in Madrid with his Spanish counterpart.

It was the second day in a row that the Saudi minister railed against Hezbollah.

On Thursday, he called the group a "first-class terrorist organisation" that should lay down its arms and respect Lebanon's sovereignty. Saudi Arabia has already asked its nationals to leave Lebanon.

Mr Hariri will go to France following a French invitation, which appears aimed to end speculation about him being held against his will.

France, Lebanon's former colonial ruler, has been trying to mediate the crisis and Mr Macron invited Mr Hariri and his family to the country after his foreign minister met with Saudi King Salman and Crown Prince Mohammed bin Salman about the crisis.

Mr Hariri's Future TV in Lebanon said he will leave Saudi Arabia on Friday night.

Meanwhile, Russia's Foreign Minister Sergey Lavrov warned against foreign interference in Lebanese affairs following Mr Hariri's resignation.

At a meeting with his Lebanese counterpart, Gibran Bassil, Mr Lavrov said: "Russia invariably stands for supporting the sovereignty, unity and territorial integrity of Lebanon."

He added that the crisis should be settled internally in Lebanon, without foreign interference, and through dialogue.

AP/Reuters