Pyongyang's Workers' Party newspaper Rodong Sinmun stated Tuesday North Koreans must defend Kim with their lives in an article marking the 54th anniversary of former leader Kim Jong Il's 1964 entry into the central committee of the party.
"In the face of any kind of adversity, we must protect Supreme Leader Comrade [Kim Jong Un's] life with ours, and on the principle of political ideology," the newspaper stated.
The article was published the same day Chinese state media reported Kim was in China on what is his third visit to North Korea's most important partner.
Sources in the country say Kim's frequent trips overseas are also being accompanied by greater state control over officials and the general population.
A North Korean source in one of the two Hamgyong provinces told Daily NK on Tuesday, ahead of his Singapore summit with U.S. President Donald Trump, Kim heightened surveillance of senior military officials and confiscated their mobile phones.
"Before he left the country for talks with the United States, Kim Jong Un implemented a thorough 'lockout' system targeting those who could potentially overthrow the state, in order to prevent a political crisis that would affect him," the source said.
The source added Kim "dragged" several military generals to Singapore so they would not plot against him in his absence.
Daily NK also reported the state instructed citizens to focus on even "higher productivity" during Kim's trip to Singapore.
Kim has said in his newly proposed strategy for economic construction that, "No matter how circumstances change, our way forward is self-reliance and self-sufficiency," according to South Korean newspaper Korea Times.
Seoul is pushing for improved communication with the North following the summit.
Yonhap reported Tuesday a North-South liaison office is under construction. South Korean officials visited Kaesong in North Korea on Tuesday to oversee the project.