No progress achieved in brief talks between two Koreas

South Korea said on Thursday that no progress was made in brief military talks it had with North Korea, local media reported.

Meanwhile, the North Koreans released the first official photograph of Kim Jong-un, their likely next leader.

During the talks, South Korea's Defense Ministry said Seoul had asked North Korea to apologize for the sinking of a South Korean warship in March, according to the Yonhap news service. South Korea also asked for punishment for those responsible for the sinking that claimed the lives of 46 sailors, New York Times reports.

The military talks come as Kim Jong Un, son of North Korea's ailing leader Kim Jong Il, was appointed to the ruling party's second-highest military position on Sept. 28, signaling preparations for a power transfer. The junior Kim, believed to be in his late 20s, was named a four-star general the previous day.

North Korea and South Korea are technically still at war since the 1950-53 Korean War ended in a cease-fire that was never replaced by a peace treaty. The U.S. stations about 28,500 soldiers in South Korea as a legacy of the war, Bloomberg reports.