In an attempt to circumvent international sanctions aimed at starving it of cash over its nuclear weapons program, North Korea has been sending hundreds of "state-sponsored slaves" to work in European Union nations, rights campaigners said Wednesday.

North Korean laborers commonly work 10-12 hour shifts, six days a week, but up to 90 percent of their pay is sent back to the hermit state, according to the European Alliance for Human Rights in North Korea (EAHRNK).

Most are working in Polish shipyards, construction sites and farms. North Koreans are also employed in leisure and clothing firms in Malta, and have worked in other EU countries, it said.