Lebanon believes Hariri is being held in Riyadh against his will

Lebanon believes Saad Hariri, who resigned as prime minister on Saturday while in Saudi Arabia, is being held in Riyadh against his will, a top Lebanese government official said on Thursday.

Hariri's shock resignation, announced on TV from Saudi Arabia, threw the Lebanese government into disarray and dragged Lebanon back into the increasingly tense regional rivalry between Saudi Arabia and Iran. 

It has fuelled speculation in Lebanon that Hariri, an ally of Riyadh, was coerced into stepping down by the Saudis.

Lebanese President Michel Aoun said Hariri's resignation will not be considered until he hears from him directly.

Iran criticised Saudi Arabia for its interference

Iran's President Hassan Rouhani criticised Saudi Arabia on Wednesday over what he called "unprecedented" interference in Lebanese affairs, adding his voice to those who suspect the Gulf kingdom forced Lebanon's prime minister to resign.

Rouhani's remarks followed a phone call to his Lebanese counterpart the previous day, in which the Iranian president pledged support for Lebanon's stability following the resignation of Saudi-backed Hariri.

Rouhani's official website quoted the Iranian president as saying "there is no case in history that a country forces another one's authority to resign only to interfere [in] their internal affairs."

Lebanon suspects Hariri resigned under duress

A second source, a senior Lebanese politician who is close to Hariri, said, "When he went [to Saudi Arabia] he was asked to stay there and ordered to resign. They ordered him to read his resignation statement, and he has been held under house arrest since."

Saudi Arabia and Hariri aides have denied reports that he is under house arrest. But he has put out no statements himself denying his movements are being restricted. He made a one-day flying visit to the United Arab Emirates earlier this week before returning to Saudi Arabia.

Saudi Arabia denies involvement

Saudi Arabia says Hezbollah, which was included in Hariri's coalition government, had "hijacked" Lebanon's political system.

In his resignation speech, Hariri attacked Iran and Hezbollah for sowing strife in Arab states and said he feared assassination. 

His father, a veteran former prime minister, was killed by a bomb in 2005.

"Lebanon is heading towards asking foreign and Arab states to put pressure on Saudi to release Prime Minister Saad Hariri," said the top government official, who declined to be identified because the government had yet to declare the initiative.

"Keeping Hariri with restricted freedom in Riyadh is an attack on Lebanese sovereignty. Our dignity is his dignity. We will work with [foreign] states to return him to Beirut."

Lebanese government has yet to accept resignation

Lebanon's foreign minister said on Thursday that the Lebanese people choose whether to remove their representatives.

"We are the ones who decided who represents us, and we are the ones who decide to remove them or not," Gebran Bassil said in a tweet.

Other officials said Hariri was still Lebanon's prime minister, echoing Lebanese government officials who say Hariri's resignation had not been received by Aoun.

Aoun wants Hariri to return to Lebanon and explain the reasons for his resignation before he will take a decision on it.

The resignation of Hariri, who is a business tycoon with major investments in Saudi Arabia, came at the same time as a wave of arrests of Saudi princes and businessmen accused of corruption by Crown Prince Mohammed bin Salman.