Iranian Supreme Leader Ayatollah Ali Khamenei has voiced support for Tehran's nuclear talks and warned against undermining diplomats engaged in the negotiations.
Khamenei was quoted as saying Iran's negotiating team is "on a difficult mission and nobody should weaken those who are on assignment."
Khamenei also said he is not "optimistic" about the talks.
But he said Iran "will not suffer losses either" if the negotiations fail.
Hard-liners in Iran have accused diplomats of being overly optimistic and keeping details of the talks secret.
The next round of talks with world powers is scheduled for November 7 in Geneva.
Khamenei has final say on all matters of state, including the country's disputed nuclear program.
The West suspects Tehran is seeking to develop a nuclear-weapons capability.
Iran denies it has such an intention and says its nuclear efforts are purely civilian.
Based on reporting by AFP, AP, and dpa