GENEVA, May 24 (Xinhua) -- UN Secretary-General Antonio Guterres said Thursday he was "deeply concerned" to hear that U.S. President Donald Trump has called off his planned Singapore meeting next month with the top leader of the Democratic People's Republic of Korea (DPRK) Kim Jong Un.

Speaking at the University of Geneva, Guterres said: "I am deeply concerned by the cancellation of the planned meeting in Singapore between the president of the United States and the leader of the Democratic People's Republic of Korea."

He urged those involved in the talks to continue their dialogue to "find a path to the peaceful and verifiable denuclearization of the Korean peninsula."

Guterres was speaking at the University of Geneva on "Securing our common future: an agenda for disarmament."

He cautioned in his speech: "We are living in dangerous times. Cold war tensions have returned -- to a world that has grown more complex."

Hours before Guterres was to deliver his speech, Trump sent a letter to Kim, saying that their planned meeting in Singapore on June 12 will not happen, according to the White House.