Google executive chairman Eric Schmidt, who wrapped up a private trip to North Korea on Thursday, is urging the reclusive communist state to allow more of its citizens to use the Internet.

Speaking to reporters at the Beijing airport, Schmidt said he used the trip to tell North Korean officials their country would have difficulty developing economically if it continues its self-imposed isolation.

Schmidt made the trip with former U.S. ambassador to the United Nations Bill Richardson, who told reporters he “strongly urged” the North Koreans to “proceed with a moratorium on ballistic missiles and possible nuclear tests.”

Richardson said the delegation was unable to meet with detained Korean-American Kenneth Bae, who North Korea has threatened to put on trial for unspecified crimes against the state.

The U.S. State Department has criticized the timing of the trip, which came as Washington and its allies push to expand sanctions against Pyongyang after its December rocket launch.

The Google delegation toured technological facilities and met with students and officials during the four-day visit, which Richardson described as “humanitarian.” Richardson says they were unable to meet with North Korean leader Kim Jong Un.

Schmidt has served as Google's main political and government relations representative and has been a vocal supporter of providing people around the world with Internet access.

Internet access is restricted to all but a tiny fraction of the most privileged and influential in North Korea. Media access is also tightly controlled, with Pyongyang demanding that all radios and televisions be pre-tuned to receive only government approved channels.