Project managers in Pyongyang have reportedly began supplying their workers with methamphetamines known as 'ice' in a bid to finish a critical showcase construction project on time, reports Daily Mail.

North Korean officials are putting extreme pressure on workers to finish frame construction on a massive set of apartments and high rises before the weather gets cold, according to Radio Free Asia, which cites multiple anonymous sources within the secretive state.

One source said: 'Project managers are now openly providing drugs to construction workers so that they will work faster.'

Hundreds of thousands of Pyongyang workers were hired for the colossal construction scheme.

According to another source, the workers face 'terrible sufferings' as pressure mounts to finish the job on time. 

The showcase will include a 70-story high-rise apartment complex and at least 60 other structures.

The construction workers are said to have graffittied several of the production signs.

One piece of graffiti proclaims 'Pyongyang speed is drug speed'. 

On another, it is written that the construction units are 'drug troops'.

The graffiti, which was found in an unfinished structure alongside empty bottles and cigarette butts, is being treated as a political crime.

Pyongyang police officers are searching for the perpetrators, according to one source: 'Investigators are warning construction workers that they will be severely punished for further incidents of this kind.'

Earlier this year, graffiti defacing North Korean leader Kim Jong-un was surfaced in Ryanggang province.

Radio Free Asia reports that residents had to provide handwriting samples to prove their innocence.