The UK said Tuesday it has started terminating “all direct air services between the UK and Iran” as part of new sanctions on Tehran for supplying Russia with missiles to use in Ukraine.

London said it was acting alongside international partners to “cancel its bilateral air services arrangements with Iran”, which would “restrict Iran Air’s ability to fly in to the UK.”

Iran Air operates direct flights between London and Tehran three days a week, according to the schedule listed on its website.

The UK move came as Western powers unveiled fresh sanctions on Iran for supplying Russia with short-range missiles for imminent use against Ukraine, calling it a dangerous escalation of the conflict that threatened European security.

The foreign ministry in London said in a statement shortly after the curbs were announced that they followed “repeated warnings” to Tehran not to transfer the deadly weapons to Russia.

“We will continue to use every lever at our disposal to put pressure on Iran to end its support for (Russian President Vladimir) Putin’s illegal invasion,” UK Transport Secretary Louise Haigh said.

“(This) is why we have begun the termination of all direct air services between the UK and Iran.”

The UK said it was also joining the United States in sanctioning “a number of key individuals and organizations for their role in facilitating Iran’s military support to Russia.”

It noted they included those involved in ballistic missile and drone supply chains.

Several Russian organizations were also sanctioned for “their intent to use the weapons systems” against Ukraine, as well as five Russian cargo ships involved in transporting military supplies from Iran to Russia.