"There must be accountability for the appalling conduct of this entire war. That is why the United Nations High Commissioner for Human Rights has rightly called for the creation of an independent body to carry out the comprehensive investigation of alleged violations of international humanitarian and human rights laws," the UN chief told reporters.
Ban asked the UN Human Rights Council to act on the matter and called on all the sides taking part in the war to cease hostilities and protect civilians.
Yemen has been engulfed in a military conflict between the government headed by Yemeni President Abd Rabbuh Mansur Hadi and Houthi rebels since 2014. The Houthis are backed by army units loyal to former Yemeni President Ali Abdullah Saleh.
Since March 2015, the Saudi-led coalition of mostly Persian Gulf countries has been carrying out airstrikes against the opposition Houthis at the request of Hadi.