The CEO of Raytheon Technologies told investors Tuesday that the company won’t be able to ramp up production of Stinger missiles until 2023, due to a lack of parts and materials for the weapons that Western allies have rushed to Ukraine.

Thousands of Stinger anti-aircraft missiles have been pulled from stocks across Europe and the United States and sent to Ukraine, but as yet there is no solid plan to replenish the stocks for the countries that donated them.

Raytheon chief warns of delays in replenishing Stinger missile stocks