Iran blamed the United States on Monday for the slow pace of indirect talks on reviving a 2015 nuclear deal.
"The main reason behind the slow pace of the Vienna nuclear talks is the United States' lack of readiness," said Iranian Foreign Ministry Spokesman Saeed Khatibzadeh.
He also ruled out any US preconditions for reviving the nuclear deal, including the release of US prisoners jailed held in Iran.
"Iran has never accepted any preconditions by the United States... The US official's comments on the release of US prisoners in Iran is for domestic use," Khatibzadeh told a weekly news conference.
The US lead negotiator in indirect talks with Iran on reviving the nuclear pact said on Sunday that Washington was unlikely to strike an agreement with Tehran unless it released US prisoners jailed in the Islamic Republic.
