NORTH KOREA VOWED today to stage an all-out drive for prosperity as it unites behind new leader Kim Jong Un, ushering in 2012 with promises to resolve food shortages, bolster its military and defend Kim Jong Il’s young son “unto death.”

The pledge in North Korea’s annual New Year’s message comes as the country enters a new era, with Kim Jong Un installed as supreme commander of the 1.2 million-strong military and as ruling party leader following his father’s 17 December death.

On the streets of Pyongyang, the mood was more sombre than in past New Year’s celebrations, as people gathered in large crowds to pay tribute to Kim Jong Il, who ruled the country for 17 years.

This New Year’s message didn’t include the North’s routine harsh criticism of the United States and avoided the country’s nuclear ambitions, a suggestion that Pyongyang may be willing to continue talks with Washington to win food aid.

This year is a crucial one for North Korea as it tries to build a “great, prosperous and powerful nation” befitting the April 2012 centenary of the birth of national founder Kim Il Sung, the new leader’s grandfather.

“Glorify this year 2012 as a year of proud victory, a year when an era of prosperity is unfolding,” said the New Year’s message, carried by the official Korean Central News Agency.

The whole party, the entire army and all the people should possess a firm conviction that they will become human bulwarks and human shields in defending Kim Jong Un unto death.

In Pyongyang, the day was cold, snowy and gray, with splashes of bright color provided by flags, lanterns and banners reading “Happy New Near” that decorated the streets. The celebration, however, coming just three days after the official mourning period for Kim Jong Il ended, was muted, unlike past years when cheerful people in their best holiday clothes thronged the streets.

From early morning, streams of people, their expressions solemn, bowed and laid bouquets and wreaths at monuments to Kim Jong Il and Kim Il Sung.

North Korea said in the New Year’s message that it would boost its military, and boasted that it is “at the epochal point of opening the gates of a thriving country,” with parts of Pyongyang “turned into socialist fairylands.”

Still, the message acknowledged the country’s food crisis, saying “the food problem is a burning issue.”North Korea had been in talks with the United States on food aid, but they stopped because of Kim Jong Il’s death.

The United Nations has said a quarter of North Korea’s 24 million people need outside food aid and that malnutrition is surging, especially among children.

The message, a joint editorial appearing in the Rodong Sinmun, Joson Inmingun and Chongnyon Jonwi newspapers, said North Korea must build on foundations laid last year and turn itself “into an economic giant.”

The traditional New Year’s Day message is closely watched for clues to the government’s plans. It takes on added significance this year, coming just two weeks after the death of Kim Jong Il.

North Korea in recent days has cemented Kim Jong Un’s position as its new leader, and on Saturday officially named him supreme commander of the military.

“The entire army should place absolute trust in and follow Kim Jong Un,” the New Year’s message said.

It linked Kim Jong Un to the “songun,” or military-first, policy of Kim Jong Il, and called him “the eternal center” of the country’s unity.

The message spoke of a desire for reunification with South Korea — a point North Korea often mentions — but did not give specifics. The North warned Friday that there would be no softening of its position toward SouthKorea’s government after Kim Jong Il’s death.

North Korea, which has tested two atomic devices since 2006, has said it wants to return to long-stalled talks on halting its nuclear weapons program in return for aid. Washington and Seoul, however, have insisted that the North show progress on past disarmament commitments before negotiations can resume.

The six-nation nuclear talks involve the two Koreas, the United States, China, Russia and Japan.

Kim Jong Un also received a boost from China, his country’s biggest backer, as President Hu Jintao sent congratulations to Kim on his appointment as supreme military leader.

North Korea’s Kim Jong Un spent part of New Year’s Day visiting a tank division in his first apparent field inspection of the country’s military since his father’s death.

By Foster Klug, Hyung-jin Kim and Scott McDonald