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The US and allies announced a new flurry of sanctions on Iran on Thursday, going after the drone industry at the heart of its military footprint in the Middle East.
A shell company known as Sahara Thunder is accused by the US of working for Iran's military to supply combat drones abroad.
An Iranian drone maker, senior business figures and shipping services used to transport military cargo have also been hit with US sanctions.
Britain is meanwhile sanctioning two people and four companies it says are involved in the Iranian drone industry behind its recent attack on Israel. New sanctions are also expected from Canada.
"We will continue to tighten the net on Iran’s ability to develop and export these deadly weapons," said UK Foreign Secretary David Cameron.
Iran fired more than 300 drones at Israel on April 13 in a retaliation of unprecedented scope for an attack on a consulate in Damascus.
Tehran has also angered western powers by supplying drones to Russia and helping Middle East paramilitaries such as Hezbollah and Yemen's Houthis.
Brian Nelson, a US Treasury under secretary in charge of terrorism and financial intelligence, said Iran "continues to destabilise the region and the world".
"The United States, in close co-ordination with our British and Canadian partners, will continue to use all means available to combat those who would finance Iran’s destabilising activities," he said.
Sahara Thunder is accused of playing an "instrumental role" in the sale of drones, for instance, negotiating with Russian officials.
Three senior figures from the company have been listed along with members of a "vast shipping network" used to transport goods.
Top officials from Iranian drone maker Bonyan Danesh Shargh have also been sanctioned after it allegedly acted as an intermediary for Iran's Islamic Revolutionary Guard Corps.
Debate in Europe
Germany has meanwhile again stopped short of classifying the IRGC as terrorists, amid fears of torpedoing nuclear diplomacy.
MPs rejected two opposition motions on Thursday calling for a tougher Iran policy to include an IRGC terror listing.
Senior figures in the government say a court decision linking the IRGC to terrorism is needed for such a designation.
This requirement has so far not been met in the eyes of EU diplomats despite a German proposal to study a 2022 attack on a synagogue, found by judges to have been organised by the Iranian state.
Despite anger in Berlin at Iran's attack on Israel and its crackdown on dissent at home, there is also concern about shutting down channels of communication with Tehran.
"To prevent the atomic programme, diplomacy is the means of choice," said Nils Schmid, an MP from Chancellor Olaf Scholz's Social Democratic Party.
"What would be the alternative to actually prevent the bomb falling into the hands of this terror regime? The truth is it would be a large-scale military action ... I have heard nobody who demands this."
Members of the European Parliament in Strasburg meanwhile voted by an overwhelming majority to condemn Iran’s attack against Israel on April 13
They called on “all parties to avoid any further escalation" as they welcomed tougher EU sanctions as a result of the attack.
EU states recently agreed to expand a sanctions regime on Iran for providing drones to Russia to cover its support for Middle East paramilitaries such as Hezbollah.
The European Parliament also asked EU diplomats to list the IRGC as a terrorist organisation, a request that has been recently pushed by the Israeli government.
The IRGC is already listed under various sanctions frameworks, including for human rights violations.
