"RIO de JANEIRO -- The Rio+20 Secretary-General said today that the absence of such world leaders as U.S. President Barack Obama, German Chancellor Angela Merkel and UK Prime Minister David Cameron will not undermine the sustainable development summit later this month."
"'I do not think the absences will weaken the final document of Rio +20 because the United States, UK and Germany will be well represented at a high level,' said Sha Zukang, the UN under-secretary-general for economic and social affairs who is responsible for the summit.
Sha made the comment after meeting this afternoon with the Rio Mayor Eduardo Paes about the logistical details of the Rio +20 summit.
According Sha, 134 heads of state or government have already registered to attend the Rio+20 summit. World leaders will be at the high-level portion of the summit June 20-22."