Russia has doubled the production of missiles for its air defense systems, Defense Minister Sergei Saigu said on Tuesday, inspecting factories in the defense industry sector in the Urals city of Yekaterinburg, according to his services.

The minister also welcomed the increase in production of the S-300 and Buk missile systems. They are expected to enter service by 2024, Mr. Saigu added, declining to disclose specific numbers.

“There has been a big increase in production volume. We have more than doubled the production of the missiles we need for air defense. But there are key issues we need to address. We have the issue of engines and the issue of speeding up the production of launch systems,” he said, according to videos uploaded by his services to the Telegram platform.

Lately, Russia’s integrated air defense systems seem not always able to prevent Ukrainian drone attacks, for example those against a liquefied natural gas (LNG) terminal in the Baltic or the one against a refinery in the Black Sea.

According to the Interfax news agency, Mr. Saigu also inspected a factory that produces systems that Ukraine struggles to defend against, such as the Iskander surface-to-surface missile and the Kalibr cruise missile.