North Korea has freed three US citizens from prison, according to a tweet from US President Donald Trump.

It is viewed as a goodwill gesture ahead of a historic summit between Trump and North Korea’s Kim Jong-un. Trump said he would greet the men when they return with Secretary of State Mike Pompeo, who has been in Pyongyang to arrange the planned talks.

The white house stated Kim Hak-song, Tony Kim, and Kim Dong-chu were able to “walk on the plane without assistance”. They had been jailed for anti-state activities and placed in labor camps.

I am pleased to inform you that Secretary of State Mike Pompeo is in the air and on his way back from North Korea with the 3 wonderful gentlemen that everyone is looking so forward to meeting. They seem to be in good health. Also, good meeting with Kim Jong Un. Date & Place set.

— Donald J. Trump (@realDonaldTrump) May 9, 2018