PYONGYANG, North Korea, Nov. 24 (UPI) -- North Korean leader Kim Jong Un's envoy, Choe Ryong Hae, returned Monday from a week-long visit to Russia.
The contents of the letter were not known although there was speculation it concerned a possible 2015 summit to strengthen bilateral relations between the two countries.
"Should North Korea and Russia form an anti-West, anti-U.S. alliance, this would bring about a significant change in the contours of regional security," said Cheong Seong-chang, a North Korea expert with the Sejong Institute.
The diplomatic trip comes amid cooling ties with China.
"Our government views the dispatch of Choe Ryong Hae to Russia as in line with (Pyongyang's) attempt to diversify its external relations," South Korean Unification Ministry spokesman Lim Byeong-cheoi said at a press conference last week.
Choe, one of Kim Jong Un's closest aides, was accompanied by Vice Foreign Minister Kim Kye Gwan, Vice Economy Minister Ri Kwang Gun, and No Kwang Chol, deputy chief of the General Staff of the North's military.