PYONGYANG, North Korea - North Korea hailed Kim Jong Il's son as "supreme leader" of the 1.2-million-strong military, ramping up its campaign to install the young man as its next leader even as the mourning continued for his father, who died a week ago.

Kim Jong Un made a third visit Saturday to the palace where his father's body lay in state - this time as "supreme leader of the revolutionary armed forces" and accompanied by North Korea's top military brass, according to the official Korean Central News Agency.

The new title and public show of support from the military leadership sent a strong signal that North Korea will maintain Kim Jong Il's "military first" policy for now.

On Sunday, North Korea's state TV aired footage showing Kim Jong Un's uncle and key patron, Jang Song Thaek, wearing a military uniform with a general's insignia - a strong sign he'll play a greater role in moves meant to secure the young Kim's rise to power.

The newspaper Rodong Sinmun, mouthpiece of the ruling Workers' Party, urged Kim Jong Un earlier to accept the top military post: "Comrade Kim Jong Un, please assume the supreme commandership, as wished by the people."

Kim Jong Un, who is in his late 20s and was introduced in September 2010 as his father's choice as successor, will be the third-generation Kim to rule the nation of 24 million. His father and grandfather led the country under different titles, and it remains unclear which other titles will be bestowed on him.

Kim Il Sung, who founded North Korea in 1948 and died in 1994, retains the title of "eternal president."

Son Kim Jong Il ruled as chairman of the National Defense Commission, supreme commander of the Korean People's Army, and general secretary of the Workers' Party.

Kim Jong Un was promoted to four-star general and appointed a vice chairman of the Central Military Commission of the Workers' Party. He had been expected to assume other key posts while being groomed to succeed his father.

His father's death comes at a sensitive time for North Korea, which was in discussions with the United States on food aid and restarting talks to dismantle the country's nuclear-weapons program.

Chronically short of food and suffering from a shortfall in basic staples after several harsh seasons, officials had been asking for help feeding its people even as North Koreans prepared for 2012 celebrations marking Kim Il Sung's 100th birthday.

North Korea has emphasized the Kim family legacy during the speeded-up succession movement for Kim Jong Un. State media invoked Kim Il Sung in declaring the people's support for the next leader, comparing the occasion to Kim Jong Il's ascension to "supreme commander" 20 years ago.

At the Kumsusan Memorial Palace, Kim Jong Un and senior commanders paid silent tribute to Kim Jong Il, "praying for his immortality," KCNA said.

The official mourning period lasts until after Kim Jong Il's funeral Wednesday and a memorial Thursday.