WASHINGTON - US President Barack Obama will visit the demilitarized zone (DMZ) between South Korea and the Democratic People's Republic of Korea (DPRK) on Sunday during his trip to Seoul for the upcoming nuclear security summit, White House officials said on Tuesday.

Obama will use his first visit to the heavily militarized zone to reaffirm the security alliance between the United States and South Korea, said the officials.

During his three-day travel to Seoul, Obama will also hold bilateral meetings with Chinese President Hu Jintao, Russian President Dmitry Medvedev and South Korean President Lee Myung-bak, said the officials.

Obama's visit to the DMZ comes at a sensitive time when the DPRK had announced that it will launch a satellite in April to mark the 100th birthday of its late leader Kim Il-Sung.

The United States had said that it is "very hard" to go forward with its planned food assistance to the DPRK if the latter moves ahead with the launch. But the DPRK has asserted that it is its legitimate right to launch a satellite.

Following the Korean war, the DMZ was created in accordance with the Armistice Agreement of July, 1953.

The DMZ, running along the 38th parallel north, provides a four kilometer-wide, 248 kilometer-long buffer zone between South Korea and the DPRK.