A U.N. human rights expert on North Korea says he hopes next week's U.S.-North Korea summit will lead to increased dialogue with Kim Jong Un on humanitarian issues.

Tomas Ojea Quintana told reporters in Geneva on Thursday that North Korea is struggling with a lack of food and that some 10 million people there are in need of humanitarian aid.

He says "the situation is quite critical."

Ojea Quintana said U.S. officials he has met agree that it's important to put human rights on the agenda, and that he hopes President Donald Trump will bring the issue up when he meets Kim in Singapore or at possible follow-up meetings.

He says Kim should declare a general amnesty for political prisoners, to send "a very important signal."