PYONGYANG, North Korea — North Korea’s next leader burnished his diplomatic skills today, welcoming a private South Korean mourning delegation as state media revealed a new title that gives Kim Jong Un authority over political matters.

Kim Jong Un has rapidly gained prominence since the death of his father Kim Jong Il on Dec. 17, and his brief meeting with a group led by a former South Korean first lady and a prominent business leader shows Seoul that he is assured in his new role.

State media have showered Kim with new titles.

On Saturday, the North referred to him as “supreme leader” of the 1.2 million-strong armed forces. Today, the Rodong Sinmun newspaper described him as head of the Central Committee of the Workers’ Party, which appears to make him the top official in the ruling party.

Today, a South Korean delegation bowed silently during their visit to the Kumsusan Memorial Palace, where Kim Jong Il’s body is lying in stated.

Kim Jong Un gave the South Koreans his thanks.

The lead delegates were the widow of former South Korean President Kim Dae-jung, who engineered a “sunshine” engagement policy with the North and held a landmark summit with Kim Jong Il in 2000, and Hyundai Group Chairwoman Hyun Jeong-eun, whose late husband had ties to the North.