North Koreans have been competing to show their devotion to their autocratic leader, Kim Jong-il, as a public holiday is held to mark his 61st birthday.

But the lavish celebrations were accompanied by a call to the military to be on high alert - the communist state is locked in a deepening stand-off with the United States.

All party members and workers must burn with hatred and hostility in their hearts toward US imperialists Rodong Sinmun newspaper

Parades, flower shows (featuring the flower named after him), concerts and firework displays have been held around the country.

The celebrations were held despite a serious economic crisis, in which many people are reported to have starved to death.

Pyongyang has engaged in an escalating war of words with Washington since October, when reports emerged that it had restarted its nuclear programme.

Kimjongilia

Kim Jong-il's birthday is a national holiday in North Korea, and people have long been preparing for the country's most important event.

Kim is reportedly grooming his successor

On Tuesday, about 50,000 gathered in Pyongyang to pledge their allegiance to Mr Kim, known as the Dear Leader.

During the main festivities which started at the weekend, generals read poems hailing the leader and the army organised huge fireworks displays.

Newsreaders on state television provided running commentaries for the event.

As part of the celebrations, an exhibition of 30,000 flowers - all of one variety - has opened in Pyongyang.

The Kimjongilia flowers are named after Mr Kim, and a number of government departments and army units have been reportedly competing to make the best bouquet arrangements.

Government officials also have been visiting a log-cabin on Paektu Mountain - a purported birthplace of Mr Kim, although western historians say Kim Jong-il was born in Russia's far east.

Mr Kim came to power in 1994 after the death of his father, Kim Il-sung, and a huge cult of personality has been built up around them.

Until three years ago he remained one of the world's most reclusive leaders - rarely seen, let alone heard in public.

That changed when he held a historic summit with South Korean President Kim Dae-jung, and hosted a visit by former US Secretary of State Madeleine Albright.

Earlier this year, Japanese media reported that Mr Kim's second son, 21-year-old Kim Jong Chul, is being groomed as his successor, ready to continue the communist dynasty.

Festivities overshadowed

This year's celebrations come amid a growing crisis over North Korea's nuclear programme.

The youths pledged their allegiance to the Great Leader

Last week, the International Atomic Energy Agency (IAEA) referred North Korea to the United Nations Security Council for breaking its nuclear agreements.

The state-run newspaper Rodong Sinmun, monitored by the South Korean Yonhap news agency, accused the US of pushing the dispute with Pyongyang "to the brink of war".

"All servicemen of the Korea People's Army should always be on the alert," the newspaper's editorial said.

"All party members and workers must burn with hatred and hostility in their hearts toward US imperialists."