Type 45 destroyers are being upgraded with some missiles that can be used for ballistic missile defense, though I'm not sure they can intercept an ICBM, probably not.
Unless there is something top secret that can be carried by our ships or that the US has deployed in Europe then I don't think there is much that can be done.
The US does have some ICBM defences though these were developed more with North Korea in mind, it's quite a hard task to solve and AFAIK they'll really need to launch multiple missiles in order to have a good chance of intercepting a single ICBM.
Basically, the main defence is MAD + if that breaks down then simply try to target as many Russian launchers/subs/command centres etc. as possible + hope plenty of them fail anyway.