Current leader Kim Jong Un paid tribute Monday to Kim Il Sung, his grandfather, as well as his late father, Kim Jong Il, by visiting the halls where both men lie in state. It was believed to be the young leader's first public appearance in two weeks.
Suspicions remain that the North could carry out a test of a mobile ballistic missile at any time.
Kerry said in Beijing at the weekend that the United States and China are calling on North Korea to refrain from any provocative steps -- including any missile launches.
Pyongyang made good on its promise to launch a long-range rocket around the time of Kim Il Sung's birthday last year; the rocket broke apart after launch and fell into the sea.
North Korea has made more threats since then. It launched a rocket in December that apparently put a satellite into orbit, and in response, the U.N. Security Council approved broadening sanctions against the country.
Angered by those sanctions, Pyongyang announced in January it was planning its third nuclear test and more long-range rocket launches as part what it called a new phase of confrontation with the United States.
It carried out an underground nuclear bomb test in February, resulting in even tougher sanctions. Those measures, along with joint U.S.-South Korean military exercises in South Korea, prompted an intensification in the North's threats.