United Nations spokesman Stephane Dujarric announced on Friday the UN had received "troubling reports" related to the use of cluster bombs in the capital of Yemen, Sanaa, and said that this could be a war crime.
"The Secretary-General [Ban Ki-moon] is particularly concerned about reports of intense airstrikes in residential areas and on civilian buildings in Sanaa, including the Chamber of Commerce, a wedding hall and a center for the blind," Dujarric told reporters.
"He [Ban Ki-moon] also has received troubling reports of the use of cluster munitions in attacks on Sanaa on [Wednesday] in several locations," Dujarric said. "The use of cluster munitions in populated areas may amount to a war crime due to their indiscriminate nature."
Human rights groups have accused the Saudi-led, US-supported coalition, of using cluster bombs in populated areas in Yemen.
Kenneth Roth, Executive Director of Human Rights Watch, said with a tweet, "Yemen may not like UN reporting cluster-bomb use but it happened."
— Kenneth Roth (@KenRoth) January 8, 2016
Stephane Dujarric stated that Ban was "deeply concerned about the intensification of coalition airstrikes and ground fighting and shelling in Yemen, despite repeated calls for a renewed cessation of hostilities."
The warring parties in Yemen had agreed on a seven-day ceasefire which began on Dec 15 under UN surveillance in Switzerland.
However, with no major breakthrough in peace talks, the repeatedly violated ceasefire collapsed on January 2. The first violation of the ceasefire came just minutes after it had been declared.
The Saudi Arabia led military coalition formally began its intervention in Yemen on March 25 after the Shiite Houthi rebels advanced on the southern cıty of Aden, forcing Yemeni President Abd Rabbuh Mansur Hadi to flee the city and take refuge in Riyadh.
Gulf Arab countries and the US have accused Iran of assisting the Houthi militants financially and militarily.
According to UN figures, at least 8,100 civilians have been killed in Yemen - nearly half of them civilians - and more than 27,000 have been injured since March.