US lawyers are pouring cold water on diplomats wanting to take part in a viral fundraiser for ALS, though not in time for ambassador to Israel Dan Shapiro to keep from getting soaked with ice water for the cause.

Lawyers at the State Department have banned American ambassadors and other high-profile foreign service officers from participating in the stunt, which aims to raise money and awareness for Lou Gehrig’s disease, also called amyotrophic lateral sclerosis, or ALS.

The stunt has lured athletes, celebrities, politicians and rock stars, and earlier this week Shapiro, who filmed himself getting ice water dumped on his head. Shapiro also challenged former envoy to Russia Michael McFaul and US ambassador to the UN Samantha Power.

It’s unlikely Power will get the chance, though.

In a cable sent this week to all US diplomatic missions, lawyers said the challenge runs afoul of federal ethics rules barring officials from using public office for private gain “no matter how worthy the cause.” The unclassified cable was obtained by The Associated Press Thursday.