North Korea has attacked the United States and rebuffed fresh calls from its only ally China to give up its nuclear programme.

As the sun set on Pyongyaang after a day of peaceful, nationwide colourful festivities celebrating the 101st anniversary of the birth of its founding father Kim Il Sung, the threat of a missile launch remained as its ambassador to China continued its aggressive rhetoric.

Ji Jae-ryong looks at picture albums on display at an exhibition in Beijing
Ji Jae-ryong looks at photo albums on display at an exhibition in Beijing

Ji Jae-ryong used the opening of an exhibition marking the event on Monday in Beijing to brand the US an “enemy” of the state and to boast of North Korea’s might as a “nuclear state and military power”.

“Currently, enemy powers such as the United States are exerting unprecedented military and political suppression on our country,” he said.

“But we have unswervingly demonstrated the power of a nuclear state and a military power, and firmly maintained peace and stability on the peninsula, and even in Northeast Asia and the whole world.

“And that is because we embrace comrade Kim Jong-Un as the top leader of our party and military,” he said, referring to the North’s unpredictable young new leader.

“As long as we follow the lead of comrade Kim Jong-Un, we are bound to obtain the great success of socialism,” he added.

North Koreans bow to bronze statues of Kim Il Sung and Kim Jong Il
North Koreans bow to statues of their former leaders

There has been fears North Korea might use the national holiday to demonstrate its military capability.

Tens of thousands of people gathered in the capital Pyongyang to celebrate the unveiling of new statues of Kim Il Sung and the son who succeeded him, Kim Jong Il.

But there were concerns North Korea may launch a medium-range ballistic missile as the Communist state has made a habit of linking high-profile military tests with key dates in its calendar.

The centenary of Kim’s birth last year was preceded by a long-range rocket test that ended in failure.

Earlier, Kim’s grandson and current dynastic leader Kim Jong-Un visited the Pyongyang mausoleum to pay “high tribute in humblest reverence” where his grandfather’s body lies embalmed, the official Korean Central News Agency said.

He also visited the embalmed body of his father, who died in December 2011.

Marathon North Korea
Athletes from 16 nations were cheered into Kim Il Sung Stadium

And despite North Korea’s warnings that the threat of war on the Korean Peninsula is so high it cannot guarantee the safety of foreign residents, it hosted athletes from around the world for its biggest international marathon yet ahead of the celebrations.

After racing through Pyongyang, athletes from 16 nations including hundreds of North Korean runners were cheered into Kim Il Sung Stadium by tens of thousands of spectators.

North Korea’s official media said the 26th Mangyongdae Prize Marathon was larger than previous years and that enthusiasm was “high among local marathoners and their coaches as never before”.

After the race, competitors then filled a performance hall for a gala concert featuring ethnic Korean performers brought in from China, Russia and Japan as part of the birthday events.

“The feeling is like, I came last year already, the situation is the same,” said Taiwan runner Chang Chia-che, who finished 15th.

South Korean Protesters Demonstrate On North Korea Founder's Birthday
South Koreans burn effigies of the North’s past and present leaders

Tourists too were invited to join in the birthday celebrations. Hannah Barraclough, who is a tour guide with the Koryo Group travel agency, told Sky News there was no sense of a nation on a war-footing.

“When we come here we are treated very well – they take the role of host very seriously,” she said.

The Korean peninsula has been in a state of heightened military tension since the North carried out its third nuclear test in February.

Incensed by fresh UN sanctions and joint South Korea-US military exercises, Pyongyang has spent weeks issuing blistering threats of missile strikes and nuclear war.

US Secretary of State John Kerry, in Japan on the last leg of an Asian tour dominated by the crisis, said the US was prepared to talk to North Korea if it took “meaningful steps” towards peace.

“The United States remains open to authentic and credible negotiations on denuclearisation, but the burden is on Pyongyang,” he said. “North Korea must take meaningful steps to show it will honour commitments it has already made.”