"The visit of Stephen O'Brien, the UN under-secretary-general, is slated for tomorrow. The preliminary purpose of his visit will be [to assess] the humanitarian situation in the region," the source told RIA Novosti.
On Friday, O'Brien's office stated that he would visit Ukraine to meet with government officials in Kiev and evaluate the humanitarian situation in the war-torn eastern provinces from November 2 to November 4.
Ukraine's Donetsk and Luhansk regions have been severely affected by fighting between Ukrainian troops and local independence supporters, which started in April 2014 when Kiev launched a military operation in Donbas.
According to the United Nations, some 150,000 people are not receiving monthly food distributions in southeastern Ukraine, access to water for some 1.3 million people is at risk, and over 30,000 people have not received shelter materials and the household items they urgently need.