UN Secretary-General António Guterres described his meeting with Russian President Vladimir Putin on Tuesday as "very useful."

The UN chief, who is expected to meet Ukrainian President Volodymyr Zelenskyy on Thursday, made the remarks in a CNN interview.

"The war will end when the Russian Federation decides to end it and when there is – after a ceasefire – a possibility of a serious political agreement. We can have all the meetings but that is not what will end the war," Guterres said.