A tour group that operates in North Korea has reported that tourists are no longer able to access the internet on their smartphones, using the country’s extensive 3G network.

“3G access is no longer available for tourists to the DPRK,” Koryo Tours has said. “Sim cards can still be purchased to make international calls but no internet access is available.”

The removal of 3G access to tourist clients comes less than a month after it first became available.