Kim holds talks with Xi in secret trip to China ahead of Trump summit

North Korean leader Kim Jong Un told his Chinese counterpart Xi Jinping that he is committed to denuclearisation as the dictator made a secret trip to China ahead of his landmark meeting with US President Donald Trump.

After two days of speculation, China and North Korea both confirmed that Kim had travelled to Beijing to meet Xi, with both sides seeking to portray strong ties.

Kim paid a four-day "unofficial visit" to Beijing from Sunday to Wednesday -- his first journey abroad since taking power and his first reported meeting with a foreign head of state -- at the invitation of Xi, state-run Xinhua news agency reported.

The state media confirmed the visit only after Kim had returned to North Korea.

The confirmation of the visit ended speculation about Kim's secret trip after Japanese media spotted a green train, similar to the one used by Kim's father, arriving in Beijing on Monday and departing the following day.

Though Chinese officials had refused to confirm Kim's presence, there were also reports about heavy security on the China-North Korea border and later at a a guesthouse where prominent North Koreans have stayed in the past.

During the visit, which was kept under wraps, Kim held talks with Xi at the Great Hall of the People in Beijing during which the two leaders hailed their nations' historic relations, with the North Korean leader pledging that he was "committed to the denuclearisation" of the Korean peninsula, Xinhua reported.

Xi and his wife Peng Liyuan held a welcoming banquet for Kim and his wife Ri Sol Ju and watched an art performance together, the report said.

During the talks, Xi welcomed Kim warmly and appreciated his congratulatory message greeting him for his re-election as the General Secretary of CPC and head of the military as well as president for the second five-year term, the report said.

Xi said Kim's current visit to China had come "at a special time" and was of great significance.

"We speak highly of this visit," Xi told Kim.

Xi underscored the importance of developing ties, saying it was "a strategic choice and the only right choice," according to Xinhua.

The Chinese leader said he was willing to maintain frequent contact with Kim "under the new circumstances".

Kim was quoted as saying that his country wants to transform ties with South Korea into "a relationship of reconciliation and cooperation."