French Foreign Minister Laurent Fabius has said it was unclear whether an international deal could be reached on Iran's nuclear program by a June 30 deadline.
Speaking in Jerusalem on June 21, Fabius said, "We need to be extremely firm. At the stage where we are now, things are still not clear."
"We think that we must be extremely firm and that, if an agreement is to be reached, that agreement must be robust," he added.
Fabius and other European foreign ministers are expected to meet Iranian Foreign Minister Mohammad Javad Zarif in Luxembourg on June 22 ahead of the final round of talks on Iran's nuclear program, which begin later in the week.
Tehran and six world powers -- the United States, China, Russia, France, Britain, and Germany -- are negotiating a comprehensive deal aimed at getting Iran to curb its nuclear activities in exchange for sanctions relief.
The six want limits on Tehran's programs that could have a military use. Tehran denies it is pursuing such weapons.