The design of the missile fired at Ukraine is based on a longer-range Russian intercontinental ballistic missile, or ICBM, the US military says, and can carry nuclear warheads

• Putin says Russia fired experimental ballistic missile into Ukraine

The United States believes Russia fired a never-before-fielded intermediate-range ballistic missile on Thursday in its attack on Ukraine, an escalation that analysts say could have implications for European missile defences.

Here’s what we know so far about the missile.