France on Tuesday said proposals submitted by Iran during talks in Vienna last week geared towards reviving the 2015 nuclear deal fall well short of what is required.

"The proposals presented by Iran last week do not constitute a reasonable basis that is compatible with the objective of a rapid conclusion while respecting the interests of all," a statement from the French foreign ministry said.

France also expressed concern and disappointment that time was running out and negotiations failed to advance with Iran's atomic drive heading in an "extremely worrying direction".

"None of the delegations present, apart from Iran, wanted the negotiations to restart on this basis."

"Time is running out then because, five and a half months after Iran halted negotiations, they still have not really resumed."

Last week, diplomats agreed to delay the discussions for several days to give room for further consultations. There is no clear timeline of when they will resume.

After the talks, the U.S. cautioned that it would not allow Iran to "slow walk" the negotiations to revive the deal. The 2015 nuclear deal has stagnated since former U.S. president Donald Trump withdrew from the pact in May 2018.

Trump's successor, Joe Biden, has said he is ready to re-enter the agreement so long as Iran meets key preconditions including full compliance with the deal, whose terms it has repeatedly violated by ramping up nuclear activities since Trump pulled out.

But Iran has been insisting that Washington should lift all sanctions imposed on Tehran and "recognise its fault in ditching the pact".

On Saturday, a senior U.S. State Department official said Iran had walked back all compromises made in previous talks on reviving the deal, pocketed compromises made by others and demanded for more in its latest proposals.

(With input from agencies)