SEOUL – Retired U.S. basketball star Dennis Rodman apologised on Thursday for suggesting that an American jailed by North Korea was himself to blame for landing in prison, adding that he was upset at the time and had been drinking.

Rodman, who calls himself a friend of North Korean leader Kim Jong Un, caused a furor with his comments on Kenneth Bae, an American missionary imprisoned by Pyongyang. Rodman is visiting North Korea with a group of fellow U.S. basketball players.

"I want to apologise. I take full responsibility for my actions, Rodman said in a statement issued by his American publicist.

"It had been a very stressful day. Some of my teammates were leaving because of pressure from their families and business associates," Rodman said. "My dreams of basketball diplomacy were quickly falling apart. I had been drinking. It's not an excuse but by time the interview happened I was upset. I was overwhelmed."

He added: "I embarrassed a lot of people. I'm very sorry. At this point I should know better than to make political statements. I'm truly sorry."

Rodman's current visit to North Korea, his fourth, has drawn criticism from human rights activists and Bae's family after he appeared to suggest in an interview peppered with obscenities that Bae, rather than the North Korean authorities, was responsible for his incarceration.

Bae's sister, Terri Chung, has said her family was outraged by Rodman's comments and that he should use his access to the North Korean leader to advocate on Bae's behalf, rather than "hurl outrageous accusations."

"It is clear to me, however, that there is nothing diplomatic about his trip," she said in a statement earlier on Thursday. "He is playing games with my brother's life."

But Chung later issued a separate statement saying that her family had accepted Rodman's apology.

"As Rodman has stated, being drunk and stressed is not an excuse for what he said, but we acknowledge he is human and we all do make mistakes," Chung said.

"Our greatest concern remains the health and freedom of my brother Kenneth," she added. "We hope and pray that Rodman's comments and ongoing antics have not further endangered my brother. Kenneth's health and freedom are precarious."

Bae, 45, was sentenced to 15 years of hard labor for state subversion in North Korea, where he was detained in 2012 while leading a tour group. North Korea's Supreme Court said he used his tourism business to form groups aimed at overthrowing the government.

'Happy birthday' to Kim

On Thursday, Rodman accompanied Kim on a trip to the Masik Ski Resort.

A source with direct knowledge of Rodman's itinerary said the 52-year-old took a helicopter to a multibillion-dollar, luxury ski resort that is seen as one of Kim's showcase projects, but which has been condemned by some observers as a waste of money in a country where most of the population is malnourished.

The source declined to be identified due to the sensitivity of the issue.

On Wednesday, Rodman led a chorus singing "Happy Birthday" to the leader of the heavily sanctioned country at a basketball match that Kim attended with his wife.

North Korean state media said the song was "reflecting (Rodman's) reverence" for Kim Jong Un, and that he had organised the game as a gift for his birthday, confirming for the first time the leader's date of birth. He is believed to be 31.

The Rodong Sinmun, the official newspaper of North Korea's ruling Workers' Party, dedicated its front page to coverage of the basketball game and published photos of Kim sitting and laughing with Rodman.

"Dennis Rodman said he was overjoyed and teared up when he met the Dear Respected Marshal again," the newspaper said.

The fading basketball star's trips had previously been financed by Irish bookmaker Paddy Power, although it has now withdrawn its funding.

It is not known whether Rodman has the capacity to fund another trip. North Korea rarely pays for this kind of visit, according to experts on the country.

Rodman has described Kim, who has been in power for just over two years, as his friend.

Kim has presided over two long-range rocket launches - banned under U.N. sanctions due to Pyongyang's nuclear weapons and proliferation efforts - a nuclear test and last year threatened to attack South Korea, Japan and the United States.

Last month, his uncle Jang Song Thaek was executed in one of the biggest and most public purges undertaken in North Korea, which has been ruled by the same family for three generations.

While North Koreans suffer from food shortages and malnutrition, according to U.N. assessments, Kim has pushed ahead with big building projects such as the Masik Ski Resort.

South Korean officials estimate it cost hundreds of millions of dollars to build and North Korea aims to make $43.75 million in annual profit from the resort, according to documents prepared for potential foreign investors. It expects up to 5,000 skiers to visit per day.