A missile unveiled by Iran is launched in an unknown location in Iran in this picture received by Reuters on August 20, 2020. WANA (West Asia News Agency) via REUTERS

Washington on Wednesday imposed sanctions on a procurement agent in Iran and his companies and accused them of helping to support Tehran’s ballistic missile program following missile attacks by suspected Iran-backed proxies against countries in the region.

In a statement issued as talks stalled on reviving the 2015 Iran nuclear deal, the US Treasury Department cited Iran’s March 13 missile attack on Erbil in Iraq and an “Iranian enabled” Houthi missile attack on Friday against a Saudi Aramco facility as well as other missile attacks by Iranian proxies against Saudi Arabia and the United Arab Emirates.

It accused the agent Mohammad Ali Hosseini and his network of companies of procuring ballistic missile propellant-related materials for the Islamic Revolutionary Guard Corps (IRGC) unit responsible for research and development of ballistic missiles. Iran’s IRGC is subject to US sanctions.

The Iranian mission to the United Nations did not immediately respond to a request for comment.

A US official, speaking on condition of anonymity, said the sanctions were unrelated to efforts to revive the nuclear deal under which Iran had limited its nuclear program to make it harder to develop a nuclear bomb in return for relief from global economic sanctions.

The sanctions freeze any US assets of those targeted and generally bars Americans from dealing with them. Those that engage in certain transactions with them also risk being hit with sanctions, the Treasury said.

The network of companies includes Iran-based Jestar Sanat Delijan and Sina Composite Delijan Co. Also sanctioned was P.B. Sadr Co, which the Treasury accused of acting on behalf of Parchin Chemical Industries, an element of Iran’s Defense Industries Organization also under US sanctions.

A nascent plan for Iraq’s Kurdish region to supply gas to Turkey and Europe — with Israeli help — is part of what prompted Iran to strike Erbil with ballistic missiles this month, Iraqi and Turkish officials say.

The Houthis said they launched attacks on Saudi energy facilities on Friday and the Saudi-led coalition said oil giant Aramco’s petroleum products distribution station in Jeddah was hit, causing a fire in two storage tanks but no casualties.

The indirect US-Iran nuclear talks were nearing an agreement in early March before last-minute Russian demands for sweeping guarantees that would have hollowed out sanctions imposed following its invasion of Ukraine derailed the talks.

Russia has since appeared to have narrowed its demands to cover only work linked to the nuclear deal, leaving a small number of issues to be resolved between Washington and Tehran, diplomats say.

US Secretary of State Antony Blinken sought to assure Gulf monarchies on Tuesday that Washington is determined to help them fend off attacks from the Iran-aligned Houthi group in Yemen.

Blinken met Abu Dhabi Crown Prince Sheikh Mohammed bin Zayed al-Nahyan, de facto ruler of the United Arab Emirates, in Morocco as part of a trip to the Middle East and North Africa.

Gulf states have for years been frustrated by what they see as US inaction in confronting Iran’s role in the region, but their concerns have grown since Joe Biden became president 14 months ago.

Israel and some Gulf nations fear that a revived nuclear deal would give Iran more oil revenues that it could use to support regional proxies, potentially leading to more attacks on them.