Hardline protesters in Tehran on Saturday suggested Iran’s negotiators lack the backing of Supreme Leader Mojtaba Khamenei, pointing to his public silence on ongoing talks with the United States, according to reporting from Iran International.

During demonstrations opposing negotiations, protesters carried signs questioning why Khamenei had not publicly endorsed the diplomatic effort.

“Imam Mojtaba Khamenei even issued a message about a plane tree for Nature Day,” one placard read. “How come he has not said a single sentence about approving negotiations?”

The protest comes as U.S. and Iranian officials signal a potential agreement could be near, while opposition from hardline factions inside Iran appears to be growing.