BEIJING >> Three Nobel laureates in science and economics who visited North Korea last week for what was billed as an educational exchange said Saturday that they had met university students who were eager to learn, but who were hampered by the North’s tight internet controls and by rudimentary, decades-old equipment.

Two of the laureates, Aaron J. Ciechanover of Israel, a biologist, and Sir Richard J. Roberts, the chief scientific officer at New England Biolabs in Massachusetts, said at a news conference in Beijing that they had invited North Korean students to come and work in their laboratories. But that prospect appeared unlikely.

The weeklong visit by Ciechanover, Roberts and a third laureate, Finn Erling Kydland, a Norwegian who shared the Nobel for economics in 2004, was organized by the Vienna-based International Peace Foundation and by the National Peace Committee of Korea, an organ of North Korea’s ruling Workers’ Party. The trip, which ended Friday, was authorized by Kim Yong Nam, the president of North Korea’s Supreme People’s Assembly, and was intended as an exchange of educational views, the organizers said.

On Friday, the Workers’ Party opened its first congress in 36 years in Pyongyang, the North Korean capital, but the timing was coincidental, said Uwe Morawetz, the chairman of the International Peace Foundation. He said the South Korean ambassador in Bangkok had asked that the trip be delayed until after the congress, which is a major propaganda event for North Korea’s top leader, Kim Jong Un, but that the organizers had declined to do so because the visit had been planned long in advance.

The Obama administration made no attempt to discourage the trip, Morawetz said.

The laureates gave lectures at the isolated country’s top universities, all in Pyongyang: Kim Il Sung University, Pyongyang University of Science and Technology, and Kim Chaek University of Technology. At the news conference Saturday, the laureates described highly motivated students who were hindered in part by their government’s policies.

“The best thing we found was that the students were knowledge-hungry,” said Ciechanover, a professor at Technion Israel Institute of Technology in Haifa, who shared the Nobel for chemistry in 2004. “The English was striking. In two of the three universities, we did not need translation.”

But the North’s restrictions on the internet made it virtually impossible for the students to progress, the scientists said. The level of research was “less than basic,” Ciechanover said.

Student researchers had access to a so-called e-library through which they could ask supervisors for documents from the web, which would then be sent to them through the university’s internal internet system, the scientists said.

One student’s work, on adapting a herbicide for spraying on crops, showed such promise that Ciechanover said he had invited him to his institute in Haifa. Similarly, Roberts, a British citizen who shared the Nobel for medicine in 1993, said he had invited a student to his laboratories in Massachusetts. The U.S. government might need some “prodding” to allow that student into America, he said.

The North Korean authorities, asked whether the students could come to Israel and the United States, said students would only be allowed to travel outside the country in pairs, Roberts said. That rule is meant to discourage defections.

The laureates are unlikely to have met average North Koreans during their trip. University students, particularly at prestigious campuses in Pyongyang, are screened for loyalty to the government, and foreign visitors are typically accompanied by government minders.

North Korea’s nuclear weapons program was not discussed during the visit, said Morawetz, who said he had deliberately chosen Nobel laureates for the visit who were not involved in physics or nuclear research.

But the laureates suggested Saturday that the U.N. sanctions imposed on the North because of its nuclear program should be eased. At the Okryu Children’s Hospital in Pyongyang, a showcase medical center that Kim Jong Un visited during its construction in 2013, Ciechanover said that there were 300 beds and a capacity for 300 outpatients, but that doctors administered only about 60 tests a day, a low figure that he attributed to the sanctions. Doctors faced shortages of medicine and took the view that “you give only what you have to,” he said.

The U.N. sanctions do not apply to medicine, but they restrict the North’s access to foreign currency, and the government is known to channel its limited resources toward the military.

The laureates suggested that the sanctions, which were tightened in March in response to North Korea’s fourth nuclear test in January, would not lead to regime change or to the North’s abandoning its nuclear weapons. “They say: ‘We are self-sufficient. We don’t need you.’ I got the impression they make them stronger,” Ciechanover said, referring to the sanctions.

The International Peace Foundation usually receives corporate sponsorship for its work in Asia, but the North Korea trip failed to attract backing, Morawetz said. The laureates paid their own airfare and were provided accommodation in guesthouses by the North Korean government, he said.

© 2016 The New York Times Company