Through a statement issued by his spokesperson Stephane Dujarric on Saturday, the UN chief fully supported the call made by the co-chairs of the OSCE Minsk Group for an immediate humanitarian ceasefire, as agreed in Moscow on October 10, and confirmed subsequently in Paris on October 17 and in Washington on October 25.
"The Secretary-General remains deeply concerned by reports of continuing hostilities, which continue to affect civilians.
"He condemns all such attacks and reiterates that both sides have the obligation, under international humanitarian law, to take utmost care to spare and protect civilians and civilian infrastructure in the conduct of military operations," said the statement.
"The Secretary-General calls on the sides to implement, in good faith and on an urgent basis, the concrete steps they agreed to take through the facilitation of the OSCE Minsk Group Co-Chairs, as well as their previous commitments."
It added that Guterres urged the sides to continue engaging in a substantive dialogue and to intensify their efforts with the facilitation of the co-chairs to reach a peaceful and sustainable settlement of the conflict.
Foreign ministers of Armenia and Azerbaijan on Friday reached an agreement on not targeting civilian population and non-military objects in accordance with international humanitarian law, said a joint statement issued by the co-chairs of the OSCE Minsk Group.
Armenia and Azerbaijan have been at loggerheads over the mountainous region of Nagorno-Karabakh since 1988.
Peace talks have been held since 1994 when a ceasefire was reached, but there have been sporadic minor clashes.
A new round of armed conflict broke out along the contact line on September 27.