Mugabe was offended when three Western envoys that were attending the funeral stood up and left during the middle of the funeral ceremony.
Mugabe's speech upset the EU, German and US envoys so much so, they left the ceremony refusing to listen to the ideas that Mugabe expressed.
Mugabe and other officials in Zimbabwe are saying the behavior of these envoys was unprofessional and unacceptable. At least one of those who left the ceremony feels the same about Mugabe.
US Ambassador Charles Ray has refused to apologize.