Chris Llewellyn Smith headshot photo.
Photo credit: University of Oxford

CERN and SESAME – Science Diplomacy Building Bridges

#SciDipTurns10 CERN SESAME Russia Ukraine Broader Middle East and North Africa Europe

Scientists have a long tradition of maintaining lines of communication with colleagues across the world, even in dire geopolitical circumstances. CERN kept open relations across the Iron Curtain at the height of the Cold War. SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East), a facility based in Jordan, whose members include Iran, Israel, and Palestine,1 bridges deep political divides.

CERN and SESAME’s original aims were to enable construction of research facilities beyond the means of individual members and to foster cooperation between peoples recently or (in SESAME’s case) currently in conflict. Ten years ago, I hoped2 SESAME would come into operation in 2015. Despite some setbacks,3 it was commissioned in 2017. Today, 1,020 registered users carry out experiments at SESAME. Scientifically and politically, it is working, although many members find it hard to pay their modest contributions, let alone increase them, to enable the exploitation of new facilities that are being built.4

SESAME shows that people of good will can collaborate across deep political divides, but other collaborations are threatened by Russia’s invasion of Ukraine. The invasion has, for example, halted collaborations between Russia and other countries with Arctic coastlines, who were working together on issues with important implications for climate change.5

Soon after the conflict in Ukraine began, the presidents of the U.S. National Academies expressed a commitment to keeping channels of communication with Russian scientists open.6 In June 2022, however, the White House announced a winding down of collaborations with Russian government-affiliated research institutions.7 The G7 Science Ministers followed suit, albeit in more nuanced terms.8 This is a worrying development for those who have witnessed the political and scientific benefits of international collaborations.

Over 1,200 Russians (many of whom have condemned the invasion) participate in CERN’s scientific program under agreements with the Russian government and universities/research institutes whose rectors/directors have issued statements supporting the invasion.9 CERN’s members take different views on whether their participation should be allowed to continue. In June, the CERN Council declared an intention to terminate agreements with Russia and Belarus when they expire in 2024,10 while monitoring developments. This decision is already having a serious impact. I hope – but strongly doubt – that it will be reversed, and that the centuries-old tradition of scientific collaboration across divides will be maintained at CERN as it is at SESAME.


  1. The other members of SESAME, which is a third-generation light-source, are currently Cyprus, Egypt, Jordan, Pakistan, and Turkey - see A synchrotron light source produces very intense pulses of light/X-rays, with wave lengths and intensities that allow detailed studies of objects ranging in size from human cells, through viruses down to atoms, with a precision that is not possible by other means. The users of SESAME, who include graduate students, are mostly based in universities and research institutes in the Middle East and neighbouring countries. They typically visit the laboratory for a few days to up to a week or two, to carry out experiments, often in collaboration with scientists from other centres/countries. See David Shukman, “Sesame synchrotron is a flash of unity in Middle East,” BBC, November 16, 2012,
  2. Chris Llewellyn Smith, “Synchrotron Light and the Middle East: Bringing the Region’s Scientific Communities Together through SESAME,” Science & Diplomacy, Vol. 1, No. 4, November 16, 2012,
  3. Among financial setbacks, sanctions prevented Iran from fulfilling a pledge to make a special capital contribution. The collapse of the roof, caused by an unprecedented snowfall in 2013 (it snowed in Cairo for the first time in 112 years), led to additional delays. See Chris Llewellyn Smith, “SESAME - The Construction Period,”
  4. The funding problem has been eased but not solved by the construction of a solar power plant (funded by the European Union), which has reduced a potentially crippling power bill to almost zero. This has made SESAME the world’s only laboratory powered entirely by renewable energy.
  5. “Russian and Western scientists no longer collaborate in the Arctic,” The Economist, May 14, 2022.
  6. Statement from the National Academies: “‘We Stand With Our Colleagues in Ukraine,’ Say U.S. National Academies Presidents,” March 3, 2022,
  7. Statement from the White House: “Guidance On Scientific and Technological Cooperation with the Russian Federation for U.S. Government and U.S. Government Affiliated Organizations,” June 11, 2022,
  8. The G7 statement is similar to that issued by the White House but qualifies the aim of restricting government-funded research involving Russian government participation with the phrase “as appropriate.” See G7 Science Ministers, “G7 Science Ministers’ Communiqué,” University of Toronto, June 14, 2022,
  9. For a report on the statement issued by rectors see: Bredan O’Malley, “Russian Union of Rectors backs Putin’s action in Ukraine,” University World News, March 6, 2022,, and for a particularly strong statement made by the Kurchatov Institute, only available in Russian, see: Kurchatov Institute Staff, “Учёным России,” Kurchatov Institute, March 4, 2022,
  10. Statement from CERN: “CERN Council declares its intention to terminate cooperation agreements with Russia and Belarus at their expiration dates in 2024,” June 17, 2022,
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