Hariri wrote on Twitter that he was "perfectly fine" and would return, "God willing, to dear Lebanon as I promised". On Wednesday he said he would return in a couple of days but that his family was staying in Saudi Arabia, calling it "their country".
Hariri holds Saudi nationality and his family fortune is based on the construction company - Saudi Oger - built by his father Rafik al-Hariri, who served twice as Lebanese prime minister and was assassinated in 2005.
Okab Sakr, a member of parliament for Hariri's Future Movement, told Reuters he had spoken on Wednesday to Hariri and that he told him neither he nor his family were being held.
On Tuesday, European Union foreign policy chief Federica Mogherini said after meeting Bassil in Paris that she expected Hariri and his family to return to Lebanon soon.
Sources from across Lebanon's political spectrum have said Hariri struck a more compromising tone in his Sunday interview than in his resignation statement, when he bitterly attacked Iran and Hezbollah.
The sources said this represented a retreat by Riyadh attributable to Western pressure. On Wednesday, Aoun said Riyadh had not responded to Arab countries who tried to secure Hariri's return so he had asked the international community to help.
French Prime Minister Edouard Philippe called on Hariri to return to Lebanon. French Foreign Minister Jean-Yves Le Drian arrives in Riyadh late on Wednesday and is due to discuss Lebanon with Saudi Crown Prince Mohammed bin Salman and meet Hariri on Thursday, a French diplomatic source said.