A Malaysian Airlines 777 crashed in eastern Ukraine today, killing all 295 passengers and crew.
A Russian-made missile may have brought down the carrier, according to Ukrainian officials.
President Obama and Russian strongman Vladimir have discussed the incident.
Ketchum, which was called in by Malaysia Air after the loss of Flight 370 in March, also represents Russia.
London-based Perowne Charles Communications has been Malaysian Airlines' outside PR firm for the past several years and is handling the current crisis.