Foreign Minister Yun Byung-se warned Tuesday that last week's mass defection of North Korean workers from China may not be the last if Pyongyang continues to build its nuclear arsenal.

Yun's remark comes four days after Seoul announced the arrival of 13 North Korean employees from a Pyongyang-run restaurant in China. It is rare for North Koreans to defect in such a large group.

"This appears to be an example indicating that such incidents may continue if the North Korean regime continues to make the wrong choices, such as its development of nuclear weapons," he said in an address at a meeting of the Korea-Russia Dialogue's coordinating committee.

Seoul has claimed the defections show that recent U.N. and bilateral sanctions against the North are having an effect as the South's unilateral measures included a call on its citizens abroad to refrain from visiting North Korean restaurants that generate income for the Pyongyang regime. The sanctions were adopted in response to North Korea's nuclear test in January and long-range rocket launch in February.

Yun said he hopes the Korean Peninsula will see the same "wind of change" seen in the lifting of sanctions on Iran, the normalization of ties between U.S. and Cuba and the launch of a democratically elected government in Myanmar.

The minister also stressed the importance of Russia's role in resolving the North Korean nuclear issue.

"We will place importance on cooperation with Russia as much as cooperation with the U.S., Japan and China," he said, adding that he plans to visit Moscow within the year.

The minister pledged Seoul's best efforts to develop ties with Russia despite various political and economic challenges, such as low oil prices.

The Korea-Russia Dialogue was launched under the initiative of the two countries' then presidents following the September 2008 summit meeting.

It is a private-public forum made up of six subcommittees that seek to bolster ties in culture, politics, trade, science and other areas. (Yonhap)