Ruto and national broadcast director Joshua Sang are on trial at The Hague, Netherlands, for alleged war crimes committed during post-election violence in 2007. Ruto is accused of turning to violence for political gain while Sang was characterized as the "voice of hate" during the crisis.
The trial chamber said Monday it "excused Mr. Ruto from trial proceedings for one week" so he could return home to help coordinate the response to last Saturday's attack on the Westgate shopping mall in Nairobi. Militants from al-Shabaab are accused of carrying out the attack, which left more than 60 people dead.
Ruto's defense team issued a request for a longer delay so he could deal with the national response to the attack. The ICC rejected his appeal.
"The appeals chamber dismisses Mr. Ruto's request for reconsideration," a statement published online by Capital FM in Kenya read.
The African Union issued a letter to the ICC expressing its frustration with Ruto's trial. The AU said his appearance at The Hague handicapped his ability to uphold his constitutional obligations.
Kenyan President Uhuru Kenyatta is expected before court in November. All three men claim they're innocent. Ruto's trial resumes next week.