The final draft, submitted by European officials, must be signed by both U.S. President Joe Biden and Iranian President Ebrahim Raisi in the coming weeks, when the deadline for talks expires, Bloomberg reports.

On Monday, Iran’s chief negotiator in the talks returned to Tehran where the final draft will be reviewed and decided on by Supreme Leader Ayatollah Ali Khamenei.

“We worked for four days and today the text is on the table,” a European official speaking on condition of anonymity told reporters. “The negotiation is finished, it’s the final text… and it will not be renegotiated.”

The parties “now need to decide if the draft is acceptable for them,” Russian Ambassador Mikhail Ulyanov wrote on Twitter. “In case of no objection the nuclear deal will be restored.”

The original 2015 nuclear deal–signed by Iran with the U.S., France, Germany, Britain, Russia and China–was abandoned by Donald Trump in 2018. In the nearly four years since, Iran is said to have significantly ramped up its nuclear activities.

The final draft delivered by European Union officials could lead to a significant expansion of Iranian oil exports, but officials involved in the talks say that major sticking points remain.

On Sunday, just hours before talks ended in Vienna, Iranian Foreign Minister Hossein Amir-Abdollahian told UN Secretary-General Antonio Guterres that Tehran is not seeking to possess nuclear weapons.

"Nuclear weapons have no place in the doctrine of the Islamic Republic of Iran and are contrary to our policies and beliefs," Amir-Abdollahian was quoted by the ministry's website as saying, as reported by Xinhua. "The supreme leader's fatwa about the use of nuclear weapons is clear for everyone," he said.