Saad Hariri has returned to Beirut, more than two weeks after announcing his shock resignation as Lebanon's prime minister from Saudi Arabia.
He arrived in the capital's international airport late on Tuesday.
A Sunni Muslim politician and longtime ally of Saudi Arabia, Hariri announced his resignation in a televised address on November 4, shortly after landing in Riyadh.
In that speech, Hariri blamed interference in Lebanon by Iran and its Lebanese ally Hezbollah for his decision, adding that he feared an assassination attempt.
'Two weeks of uncertainty'
Hariri's resignation plunged Lebanon into uncertainty, threatening the country's fragile political stability and raising concerns over an open-ended crisis.
It also stoked fears of an escalation in the regional divide between Iran and Saudi Arabia, with Lebanon on the front lines.
Officials in Lebanon said they will only accept Hariri's resignation if he delivers it on Lebanese soil.
They also alleged that he was being held hostage by authorities in Saudi Arabia, claims Hariri has rejected.
Politicians within his own Future Movement, as well his rivals, demanded he return home to formalise his resignation.
On Saturday, after flying to Paris from Saudi Arabia to meet French President Emmanuel Macron, Hariri said he would return to Lebanon to take part in Independence Day celebrations.
"It is there that I will make known my position on all the issues," he told reporters in the French capital.
Lebanon marks its Independence Day on Wednesday.
Al Jazeera's Zeina Khodr, reporting from Beirut, said Hariri's sudden resignation has "ignited a crisis and raised a lot of questions".
"Two weeks of a lot of uncertainty, not just surrounding his resignation but about his circumstances while in Saudi Arabia," she added.
"Many in Lebanon believe that Hariri, in one way or another, was being held hostage."
Hariri is part of a unity government under President Michel Aoun that also includes rival political factions such as those supported by Hezbollah, a popular Shia group which is represented in the Lebanese parliament and has a strong armed wing.
Hassan Nasrallah, the leader of Hezbollah, has previously said he was sure Hariri was forced to resign as part of what he called Saudi Arabia's policy of stoking sectarian tensions in Lebanon.
Last week, in his first public comments since his shock resignation, Hariri said he had "complete freedom" in Saudi Arabia.
Speaking on Future TV, a station affiliated with his political party, Hariri said that upon his return to Lebanon he would confirm his resignation in accordance with the country's constitution.
Al Jazeera's Khodr said that with Hariri back in Lebanon, many believe that Aoun will try to find a compromise and persuade him to withdraw his resignation.
Aoun has also accused Saudi Arabia of holding Hariri against his will.