Eslami said "no" when asked whether Iran will exceed 60% uranium enrichment if the parties fail to return to the 2015 Joint Comprehensive Plan of Action.
He stressed that Tehran's nuclear programme aims to support the country's industrial production needs, as well as the needs of Iranian consumers for certain goods.
"All our nuclear activities are carried out according to the agreements, statutes and regulations of the International Atomic Energy Agency", the AEOI chief added.
The seventh round of Vienna talks on bringing Iran back to the nuclear deal and cancelling US sanctions ended on 17 December. The parties agreed on two drafts of the deal, which included provisions covering Iranian interests.