LONDON (AP) — The United States formally accused Iran on Tuesday of supplying short-range ballistic missiles to Russia for its war in Ukraine and will take measures to punish those involved.

U.S. Secretary of State Antony Blinken, speaking alongside British Foreign Secretary David Lammy during a visit to London, said that sanctions would be announced later Tuesday.

“Russia has now received shipments of these ballistic missiles and will likely use them within weeks in Ukraine, against Ukrainians,” Blinken said.

His comments came as he and Lammy prepare to make a joint visit to Ukraine on Wednesday.

Word of the alleged transfers began to emerge over the weekend with reports that intelligence indicated they were underway, according to U.S. officials who spoke on condition of anonymity. Blinken said Tuesday that the transfers appear to have been completed.

Iran, as it has with previous U.S. intelligence findings, has denied providing Russia with weapons for its war in Ukraine.