DVDs of Sony’s controversial film The Interview will be dropped into North Korea by balloon, a South Korean activist says.

Park Sang-hak said he hopes to break down a personality cult built around North Korea dictator Kim Jong Un.

The comedy depicting an assassination attempt on Kim is at the centre of tension between North Korea and the US, with Washington blaming Pyongyang for crippling hacking attacks on Sony Entertainment.

Pyongyang denies that and has vowed to retaliate.

Mr Park said today he will start dropping 100,000 DVDs and USBs with the film by balloon in North Korea as early as next month.

The North Korean defector said he is working with the US-based non-profit Human Rights Foundation, which is financing the making of the DVDs and USB memory sticks of the film with Korean subtitles.

He said foundation officials plan to visit South Korea around January 20 to hand over the DVDs and USBs, and that he and the officials will then try to float the first batch of the balloons if weather conditions allow.

“North Korea’s absolute leadership will be crumble if the idolisation of leader Kim breaks down,” the activist said.

If carried out, the move is expected to enrage North Korea, which expressed anger over the film.

In October, the country opened fire at giant balloons carrying anti-Pyongyang propaganda leaflets floated by South Korean activists, trigging an exchange of gunfire with South Korean troops.

But it is not clear how effective the plan will be, as very few ordinary North Korean citizens own computers or DVD players.

Owning a computer requires permission from the government and costs as much as three months’ salary for the average worker, according to South Korean analysts.

Not everyone supports sending balloons into the North, with liberals and border town residents in South Korea urging the activists to stop.

North Korea has long demanded that South Korea stop the activists, but Seoul refuses, citing freedom of speech.

Mr Park said the ballooning will be done clandestinely, with the pace picking up in March when he expects the wind direction to become more favourable.

Calls to the Human Rights Foundation were not immediately answered. Its website says it works with North Korean defectors to use hydrogen balloons to send material across the border, as well smuggling items through China and broadcasting radio transmissions to reach those who own illegal short wave radios.

Meanwhile Canadian will be able to watch The Interview by more conventional means when it is released in cinemas on Friday.

Sony Pictures said the film will open in 27 cinemas in various cities in British Columbia, Alberta, Saskatchewan, Ontario, Quebec, Manitoba and New Brunswick.

Sony initially cancelled plans to show the Seth Rogen-James Franco film because many cinemas decided not to show it.

The company later reversed that decision and the film started playing in some independent cinemas in the US.

Sony, which had received a wave of criticism after it decided not to show the film, including from President Barack Obama, also released the movie online.