Berlin - German Chancellor Angela Merkel added her voice Wednesday to calls for Zimbabwe's President Robert Mugabe to step down.

"Especially in Zimbabwe's case, we must do our very best to attain life without the terrors of President Mugabe," she said in Berlin in a speech marking the 60th anniversary of the Universal Declaration of Human Rights.

"The excuse of national sovereignty cannot be used to shelter the completely unrestrained commission of serious human rights breaches," Merkel said.

Others demanding this week that Mugabe, 84, leave have included US President George W Bush and French President Nicolas Sarkozy.

As the death toll from cholera rises into the hundreds, the demand has also been voiced by British Prime Minister Gordon Brown and Kenyan Prime Minister Raila Odinga. The UN says at least 746 Zimbabweans have died of the disease so far. dpa