In a statement released in New York yesterday, Annan's spokesperson Marie Okabe hinted that the world body may come down hard on President Mugabe's government over the demolitions.
"The secretary-general is increasingly concerned by the human rights and humanitarian impact of the recent demolitions of what the government of Zimbabwe has called illegal settlements."
The statement comes as UN envoy Anna Tibaijuka flew to New York to hand over a report on her two-week assessment of the controversial clean up exercise as international pressure mounted on Mugabe to stop the demolitions.
The UN together with the United States, Britain and human rights groups have already criticised the operation as an assault on the rights of the poor.
But Mugabe has defended the programme saying it is necessary to clean up cities which had become havens of crime in order to smash a thriving foreign currency parallel market blamed for Zimbabwe's economic woes.
Zimbabwe's main opposition Movement for Democratic Change party says close to a million people have been rendered homeless in the government crackdown.
Yesterday, former United States president Bill Clinton added his voice to the chorus of criticism of the 81-year old Zimbabwean leader urging people to speak out over Mugabe's human rights abuses. - ZimOnline