North Korean foreign minister Ri Yong-ho is reportedly headed to Stockholm to meet his Swedish counterpart.

According to diplomatic sources, Ri arrived in Beijing on Thursday to transfer to a plane bound for Sweden.

The trip has raised speculation that the Pyongyang diplomat will engage with a U.S. official during his time in the European country, ahead of the upcoming bilateral summit between U.S. President Donald Trump and North Korean leader Kim Jong-un in May.

Sweden has, in the past, been used as a contact point between Washington and Pyongyang.