The US Senate Foreign Relations Committee has asked Special Envoy for Iran Robert Malley to testify about the ongoing Vienna negotiations to revive the 2015 nuclear deal.

The briefing session to update Senators on the Vienna negotiations is scheduled to be held on Wednesday, February 9, but the hearing won't be open to the public or televised.

The session was set only a day after Senator Bob Menendez asked President Joe Biden to stop the nuclear talks and adopt a tougher position on the Islamic Republic.

Menendez, the chairman of the committee, is the first senior Democrat to challenge Biden on its policies towards Iran, saying, “We cannot allow Iran to threaten us into a bad deal or an interim agreement that allows it to continue building its nuclear capacity”.

Menendez, who opposed the 2015 Joint Comprehensive Plan of Action (JCPOA) when it was negotiated by the Obama administration, said Biden should not stick to the framework that leaves “the vast majority of Iran’s nuclear program intact”.

Earlier in January more than 100 Republican members of Congress wrote to Biden asking him to stop the negotiations and get tough with Iran, which is fast enriching uranium to higher levels.

Iran’s enrichment picked up in early 2021, after Biden said he wants to restore the JCPOA and moved toward opening talks with Iran.