"Hariri's remarks on Sunday gave small hope of the possibility of his return to Lebanon.Iran does not interfere in Lebanon's affairs", Foreign Ministry spokesman Bahram Qasemi was quoted as saying by state TV.
Several TV stations, including NBN TV, owned by Parliament Speaker Nabih Berri, didn't broadcast the Hariri interview - adopting President Michel Aoun's position that given Hariri's circumstances, "his words will not reflect the truth".
Nasrallah also said "Lebanon had enjoyed unprecedented stability over the past year".
The US has declined to comment on Hariri's status.
"[The talks] were sensitive, private, diplomatic conversations", Nauert said on Thursday. "We cannot have any more ambiguity around Lebanon's neutrality".
He also said the Saudi royal family has a "lot of respect for him" and that the King (Salman bin Abdulaziz Al Saud) "sees him as a son", brushing off concerns that he was being held against his will, CNN reported.
Nauert said Hariri's resignation was an "internal matter that we couldn't comment on". Final approval will then be sought from Lebanon's council of ministers.
The announcement from the Saudi mission at the United Nations came after the coalition fighting Yemen's rebels, known as Houthis, and their allies faced widespread international criticism over the closure, with the U.N. and over 20 aid groups saying it could bring millions of people closer to "starvation and death".
Riyadh blames Lebanon's Iran-backed Hezbollah for the resignation, accusing it of hijacking Lebanese politics.
The resignation of the Saudi-allied Hariri's and its aftermath have put Lebanon back to the forefront of the conflict between Shi'ite-led Iran and its regional Sunni rival Saudi Arabia.
Le Drian's office would not say where France's information came from.