The European Union is considering sanctions targeting Iran’s aviation sector, the bloc’s chief diplomat said on Friday in reaction to reports Tehran supplied Russia with ballistic missiles in its war against Ukraine.

US Secretary of State Antony Blinken has said Russia received ballistic missiles from Iran and would likely use them in Moscow’s war against Ukraine within weeks, a charge Iran has denied.

“The European Union has repeatedly strongly cautioned Iran against transfers of ballistic missiles to Russia,” EU foreign policy chief Josep Borrell said in a statement, adding the EU would “respond swiftly and in coordination with international partners.”