US diplomats barred from bucket challenge

Top U.S. diplomats have been barred from participating in the popular ice bucket challenge that is raising awareness for Lou Gehrig's disease. 

Citing rules that prevent using public offices for private gain, "no matter how worthy a cause," the State Department warned all high-ranking officials that they should not participate in the campaign.

The memo was sent to all State Department diplomatic stations worldwide earlier in the week, a copy of which The Associated Press obtained Thursday.

The transmission came two days after Daniel Shapiro, U.S. ambassador to Israel, participated in the campaign and challenged others — including ambassador to the United Nations Samantha PowerSamantha PowerNo, Assad is not good for Israel, and he never will be Obama's UN envoy apologizes for not recognizing Armenian mass killings as genocide New US approach to Syria a welcome sight to many in region MORE and former ambassador to Russia Michael McFaul — to do the same.

U.S. ambassador to Canada Bruce A. Heyman also participated in the challenge in honor of one of his predecessors, Paul Cellucci, who died last year due to complications from the disease. 

The agency mentioned its fight against HIV/AIDS, malaria and other diseases, and complimented the ALS Association for working to eliminate amyotrophic lateral sclerosis (ALS) but said officials could not participate out of "concerns about preference and favoritism.".

Many prominent political figures have participated in the challenge, including former President George W. Bush. Others, such as Vice President Biden, have opted to write a check instead of having ice water poured on their head.

— This story was last updated at 1:24 p.m.