The British government said on Sunday that it will develop a new deep-strike ballistic missile for Ukraine to support the country's war efforts against Russia.

Matt Korda, the associate director of the Nuclear Information Project at the Federation of American Scientists, assisted USA TODAY in identifying 50 silos near Malmstrom Air Force Base, Montana, that were deactivated in the late 2000s and later destroyed. That left USA TODAY with a list of 450 targets for our strike simulations.

Striking Russian warships immediately before the launch of sea-based Kalibr missiles is extremely difficult, as the available window is limited to just a few hours, Ukrainian Navy spokesperson Dmytro Pletenchuk said.